UHD-402MV Overview and Use Cases

What Is the UHD-402MV?

The OREI UHD-402MV is a 4K@60Hz 4x2 HDMI multiviewer and seamless UHD video matrix switcher. It allows up to four HDMI source devices to be displayed across two HDMI outputs.

The UHD-402MV can work as a standard 4-input, 2-output matrix switcher, where each output can show a selected HDMI source. It can also work as a multiviewer, where multiple HDMI inputs are combined on one screen in different layouts such as PIP, PBP, Triple, or Quad view.

The UHD-402MV supports HDMI 2.0b, HDCP 2.2 / 1.x, with a video bandwidth of 18Gbps. It supports input and output resolutions up to 4K@60Hz 4:4:4, seamless switching, 8 multiview display modes, output scaling, advanced EDID management, independent audio selection, analog RCA audio output, Optical audio output, IR remote control, OSD menu navigation, controller software, and RS-232 command control. 

The UHD-402MV is useful for control rooms, security monitoring, sports bars, conference rooms, classrooms, retail displays, worship facilities, production monitoring, and setups where multiple HDMI sources need to be viewed on one or two displays.

IMPORTANT — UHD-402MV Is a Matrix and Multiviewer

The UHD-402MV is not just a basic HDMI switch.

It supports two main functions:

This means each output can either show a single HDMI source or display a multiview layout.

IMPORTANT — UHD-402MV Supports Two HDMI Outputs

The UHD-402MV has two HDMI output ports:

• HDMI OUT 1 
• HDMI OUT 2 

Each output can be controlled independently.

For example:

• Output 1 can show HDMI Input 1 in single-screen mode 
• Output 2 can show a Quad multiview layout using HDMI Inputs 1–4 

This makes the product useful when two displays need different viewing layouts.

IMPORTANT — Multiview Mode Is Not the Same as a Video Wall

The UHD-402MV is a multiviewer, not a video wall controller.

Multiview mode combines multiple HDMI sources onto one screen.

It does not split one image across multiple displays to create one large video wall.

Use this product when you want to view multiple sources on one or two displays.

Do not use this product if you need a 2x2 video wall where four TVs act like one large TV.

IMPORTANT — UHD-402MV Supports 4K@60Hz, Not 8K or 4K@120Hz

The UHD-402MV supports video resolutions up to 4K@60Hz 4:4:4.

It does not support 8K or 4K@120Hz.

For 8K or 4K@120Hz setups, use an HDMI 2.1 switch, matrix, or multiviewer that supports the required bandwidth.

IMPORTANT — Multiview Output Is Controlled Per Output

Output 1 and Output 2 each have their own multiview control.

This means the multiview layout selected for Output 1 does not have to match the multiview layout selected for Output 2.

Use the OUT 1 Multiview button for Output 1.

Use the OUT 2 Multiview button for Output 2.

IMPORTANT — Audio Output Has Format Limits

The UHD-402MV includes separate audio outputs for Output 1 and Output 2.

If using the analog RCA L/R output, set the source audio to PCM or Stereo.

Analog RCA does not support Dolby, DTS, Dolby TrueHD, DTS-HD Master Audio, or other surround formats.

IMPORTANT — Controller Software Uses RS-232 Control

The UHD-402MV can be controlled using controller software.

The manual notes that the controller software connects through COM / RS-232 control. TCP/IP control is not supported temporarily in the controller software.

To use the controller software, connect the RS-232 port of the UHD-402MV to a PC using the 3-pin Phoenix RS-232 connection and a USB-to-RS-232 serial cable.

Default RS-232 baud rate is 115200.

Ports and Panel Layout

Step-by-Step Setup

1. Connect the included 12V/2.5A locking power adapter to the UHD-402MV. 
2. Connect your HDMI source devices to HDMI Inputs HD 1, HD 2, HD 3, and HD 4. 
   Examples include a PC, DVD player, Blu-ray player, TV box, cable box, camera system, or media player. 
3. Connect HDMI OUT 1 to your first TV, monitor, or projector. 
4. Connect HDMI OUT 2 to your second TV, monitor, or projector. 
5. If using external audio, connect the audio outputs: 
   • Use L/R OUT 1 or Optical OUT 1 for audio from Output 1 
   • Use L/R OUT 2 or Optical OUT 2 for audio from Output 2 
6. Turn on the source devices, displays, audio system, and UHD-402MV. 
7. For single-screen mode, use the OUT 1 or OUT 2 button to select the input source for each output. 
8. For multiview mode, use the OUT 1 Multiview or OUT 2 Multiview button to select the display layout. 
9. Use the RES button to set the output resolution for each output if needed. 
10. If the unit is installed where the front IR window is blocked, connect the included IR receiver cable to the IR EXT port. 
11. If using controller software or RS-232 commands, connect the RS-232 port to a PC or control system. 

HDMI Cable Requirement — Critical

For 4K@60Hz 4:4:4 performance, use high-quality HDMI cables that support HDMI 2.0 / 18Gbps bandwidth.

Poor-quality or long HDMI cables may cause:

• No video output 
• Flickering 
• Black screen 
• Audio dropouts 
• Multiview display issues 
• 4K@60Hz not displaying correctly 
• HDCP handshake problems 
• Dolby Vision / HDR issues 
• Seamless switching problems 

For troubleshooting, test each source directly with the display and try shorter HDMI cables.

Understanding Single-Screen Matrix Mode

In single-screen mode, each output displays one selected HDMI input.

Example:

Use single-screen mode when each display should show one full-screen HDMI source.

Understanding Multiview Mode

The UHD-402MV supports 8 categories of multiview display modes.

In multiview mode, users can assign HDMI inputs to different windows.

PIP mode supports input selection, sub-window size, and sub-window position.

PBP, Triple, and Quad modes support input selection, display mode selection, and aspect ratio selection.

Understanding PIP Mode

PIP stands for Picture-in-Picture.

In PIP mode, one source appears as the main image and another source appears as a smaller window.

PIP settings include:

PIP mode is useful when one main source needs to stay visible while another source is monitored in a smaller window.

Understanding PBP, Triple, and Quad Modes

PBP, Triple, and Quad modes allow multiple HDMI inputs to appear on one screen.

These modes are useful for monitoring multiple sources such as security cameras, PCs, media players, or presentation devices at the same time.

Understanding Output Resolution Scaling

Each HDMI output supports scaler function.

Available output resolutions include:

Use the RES button, OSD menu, controller software, or RS-232 command to change the output resolution.

Long pressing the RES button for 3 seconds sets the corresponding output resolution to 720P60.

EDID Settings

The UHD-402MV includes 19 EDID modes.

Use 4K60 EDID modes for modern HDMI 2.0 displays.

Use 1080p or lower EDID modes for older displays or troubleshooting.

Use Dolby/DTS 5.1 or HD Audio 7.1 modes only when the connected audio system supports those formats.

Understanding Audio Selection

The UHD-402MV supports independent audio selection.

By default, the output audio follows the video source.

Using the remote A-IN button, OSD menu, controller software, or RS-232 command, users can select the audio source for each output.

Audio source options include:

This is useful when the displayed layout has multiple sources but the user wants audio from one specific HDMI input.

Understanding Audio Outputs

The UHD-402MV includes analog and Optical audio de-embedding.

If there is no sound from the RCA L/R output, set the selected source to PCM or Stereo.

If there is no sound from Optical, make sure the connected soundbar, AVR, or amplifier supports the selected audio format.

Understanding the IR Remote

The included IR remote controls power, source selection, multiview mode, audio, mute, aspect ratio, resolution, and OSD settings.

Understanding OSD Menu Navigation

The UHD-402MV includes OSD menu navigation using the IR remote.

The OSD can control:

• Output resolution 
• VKA black screen / blue screen behavior 
• ITC video mode / PC mode 
• Multiview mode 
• Window input selection 
• PIP position 
• PIP size 
• PBP mode 
• Triple mode 
• Quad mode 
• Full / 16:9 aspect ratio 
• Audio source 
• Audio mute 
• Language 
• EDID 
• Baud rate 
• Reset 
• Firmware version check 

Use the OUT 1 or OUT 2 button on the remote to enter the OSD menu for that output.

Understanding Controller Software

The UHD-402MV can be configured using controller software connected by RS-232.

The controller software can be used to:

• View device information 
• Check input and output connection status 
• Set COM port and baud rate 
• Choose multiview mode 
• Assign HDMI inputs to windows 
• Adjust PIP size and position 
• Set aspect ratio 
• Enable or disable auto switching in Single mode 
• Set output resolution 
• Set video keep alive behavior 
• Set PC / Video picture mode 
• Set HDCP behavior 
• Choose audio source 
• Mute or unmute audio 
• Select EDID mode 
• Upgrade firmware 
• Reset to factory settings 
• Reboot the device 

The manual notes that TCP/IP control mode is disabled in the controller software at this time.

RS-232 Control

The UHD-402MV supports RS-232 command control through the 3-pin Phoenix connector.

Default RS-232 settings:

RS-232 commands can control:

• Power on/off 
• Reboot 
• Factory reset 
• Output resolution 
• Output HDCP setting 
• Video keep active pattern 
• PC / video mode 
• EDID setting 
• User EDID 
• Output audio source 
• Audio mute 
• Auto switching in Single mode 
• Input source routing 
• Multiview mode 
• Window input assignment 
• Window border 
• Border color 
• PIP position and size 
• PBP mode and aspect ratio 
• Triple mode and aspect ratio 
• Quad mode and aspect ratio 

What Source Devices Is the UHD-402MV Compatible With?

The UHD-402MV can work with HDMI source devices such as:

• PCs 
• Laptops with HDMI output 
• DVD players 
• Blu-ray players 
• TV boxes 
• Streaming devices 
• Cable boxes 
• Satellite receivers 
• Media players 
• Camera systems 
• Security DVRs 
• Presentation systems 

For 4K@60Hz 4:4:4, the source device and HDMI cable must support HDMI 2.0 bandwidth.

What Displays Is the UHD-402MV Compatible With?

The UHD-402MV can connect to HDMI displays such as:

• TVs 
• Monitors 
• Projectors 
• UHD TVs 
• Commercial displays 
• Control room displays 
• Classroom displays 
• Conference room displays 

For 4K@60Hz output, the connected display must support 4K@60Hz over HDMI.

What Audio Devices Is the UHD-402MV Compatible With?

The UHD-402MV can send audio to:

• Audio amplifiers 
• Optical soundbars 
• AV receivers 
• Powered speakers 
• 2.0 speaker systems 
• Stereo amplifiers 
• HDMI TVs or HDMI audio systems 

For analog RCA audio output, use PCM / Stereo audio.

For Optical audio output, use a format supported by the connected Optical audio device.

Frequently Asked Questions

Q: What is the OREI UHD-402MV used for? 
A: The UHD-402MV is used to connect up to four HDMI sources to two HDMI displays. It can work as a 4x2 matrix switcher or as a multiviewer that shows multiple sources on one screen.

Q: Is the UHD-402MV a multiviewer? 
A: Yes. It supports 8 multiview display modes, including Single, PIP, PBP, Triple, and Quad layouts.

Q: Is the UHD-402MV a matrix switcher? 
A: Yes. In single-screen mode, each HDMI output can select one of the four HDMI inputs.

Q: Is the UHD-402MV a video wall controller? 
A: No. It is a multiviewer and matrix switcher. It does not create a multi-display video wall.

Q: How many HDMI sources can I connect? 
A: You can connect up to four HDMI source devices.

Q: How many displays can I connect? 
A: You can connect up to two HDMI displays.

Q: Can Output 1 and Output 2 show different layouts? 
A: Yes. Each output can be controlled independently and can use its own source or multiview layout.

Q: Does the UHD-402MV support 4K@60Hz? 
A: Yes. It supports up to 4K@60Hz 4:4:4 with 18Gbps bandwidth.

Q: Does the UHD-402MV support 8K? 
A: No. It supports up to 4K@60Hz. It does not support 8K.

Q: Does the UHD-402MV support 4K@120Hz? 
A: No. It supports up to 4K@60Hz.

Q: Does it support seamless switching? 
A: Yes. The manual lists seamless switching between input channels.

Q: What multiview modes are available? 
A: The available modes are Single, PIP, PBP (1), PBP (2), Triple (1), Triple (2), Quad (1), and Quad (2).

Q: Can I show all four HDMI inputs on one screen? 
A: Yes. Use Quad mode to show four HDMI sources on one display.

Q: Can I show two sources side by side? 
A: Yes. Use PBP mode.

Q: Can I show a smaller source window over a main source? 
A: Yes. Use PIP mode.

Q: Can I change the PIP window size and position? 
A: Yes. PIP supports position and size adjustment through the OSD menu, controller software, or RS-232 commands.

Q: Does the UHD-402MV have audio extraction? 
A: Yes. It includes analog L/R RCA and Optical audio outputs for both HDMI outputs.

Q: What audio does the RCA L/R output support? 
A: The analog L/R RCA output supports PCM 2.0 only.

Q: What audio does the Optical output support? 
A: Optical supports PCM 2.0 / 5.1 / 7.1CH, Dolby Digital/Plus, and DTS 5.1.

Q: Why am I not getting sound from the RCA output? 
A: Set the selected HDMI source to PCM or Stereo because the RCA output supports PCM 2.0 only.

Q: Can I choose which HDMI source audio plays during multiview? 
A: Yes. The UHD-402MV supports independent audio selection. Audio can follow Window 1 or be manually selected from HDMI 1, 2, 3, or 4.

Q: Does it support EDID management? 
A: Yes. It supports 19 EDID modes, including 4K60, 4K30, 1080p, AUTO, and USER1.

Q: Can I change the output resolution? 
A: Yes. Output resolution can be changed using the RES button, OSD menu, controller software, or RS-232 commands.

Q: What happens if I long press the RES button? 
A: Long pressing the RES button for 3 seconds changes the output resolution to 720P60.

Q: Can I control the UHD-402MV with software? 
A: Yes. The controller software can be used through RS-232 / COM control.

Q: Does the controller software support TCP/IP control? 
A: The manual notes that TCP/IP control mode is not supported temporarily and is disabled in the controller software.

Q: Does the UHD-402MV support RS-232 control? 
A: Yes. It supports RS-232 command control through the 3-pin Phoenix connector.

Q: What is the default RS-232 baud rate? 
A: The default baud rate is 115200.

Q: What should I do if there is no video? 
A: Check that the correct input is selected, confirm the HDMI cables are connected properly, make sure the source resolution is supported, and try another HDMI cable.

Q: What should I do if the multiview layout looks stretched? 
A: Use the 16:9 button or aspect ratio settings to switch between Full and 16:9 for supported multiview modes.

Q: Does the UHD-402MV need external power? 
A: Yes. Connect the included 12V/2.5A locking power adapter.