I’m looking for anyone with knowledge of repairing a V-4EX, feel free to message me directly if that’s you.
Any help gratefully received.
Everything works except for composite input/output.
Guess what I really want? Composite i/o.
Details:
Updated to 1.530, factory reset, video inputs set to composite, hdcp off, set to ntsc for ntsc sources.
Composite input works when first turned on but then appears to lose sync and the image tears in half for a while then disappears from the input monitor.
The composite out does not send out anything.
The HDMI paths work just fine.
I am adding photos of the internals for posterity and the curious:
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Well I see your problem, the circuit boards are supposed to be inside the case! 
In your video input settings make sure you change your inputs from HDMI to composite.
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Thanks for the reply.
I put the circuit boards back where they belong.
I had changed the video input settings to composite.
I have a feeling that the chips or components which process the analog signals are duds, as some desynced visual noise comes through while VGA & hdmi work.
So it seems something is going wrong as the device warms up.
Inputs gradually fail and don’t work again until the thing is cool.
Output never really works at all.
Further diagnostic info in this video:
You’d have to trace the composite signal path from the output and from the input and see if there is continuity first off. It could be a cracked trace going intermittent or a component failing. Output could be the same, but looks like a complete failure there or a disconnected leg of something maybe.
Roland used a lot of low life electrolytic caps in their products, these might be causing a problem. though electros usually improve as they warm up whereas this is the inverse of that.
Have you got a heat gun or a can of cold spray? (dust remover will work I think for this)
After/during the trace of the composite signal path, try heating the components up or cooling them down. You can potentially find out which component is failing. Also if you have a FLIR on your camera, or a laser thermometer (failing that, your fingertips)
See which components are unusually hot.
It is more likely to be an cracked joint/ trace, electrolytic cap, transistor, diode or microchip. Resistors and ceramic capacitors, usually stay fine but they can sometimes cause problems.
Although I am sure you can figure it out - It is a job for a repair shop really, quite a few places do mail ins these days, though I don’t know any in the UK (Presuming you are in the UK)
Those components are tiny. Is the service manual available? Look for one, it will help you trace the composite path.
Is it a known issue with these devices? Have you searched for the problem online?
Often someone has fixed this issue on their own device.
good luck.
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