Never had any issues with my 161, but recently i went for a 6 slot multi jamma switcher in my cab, and it messes with the video from my MVS, causing a slight bend (betamax style!) at the top of the picture at best, and at worst, a rapid horizontal rolling! ofc, using a real cart there is no problem, and running the MVS straight into the cab's jamma harness with the 161 there is no problem.
I tried patching the (alredy modded for MVS) extender loom with beefier cables for 5 and 12v, and all the video lines, and it did seem to make a difference, but the video still goes nuts depending on the location of the MVS inside/outside the cab! maybe some induction caused by all the other stuff in there?
I see a ~.1v voltage drop on 12 and 5v between the PSU and the multi switcher, and then .1v again from the slot to the MVS itself, but it still shows 5.1V on the MVS itself and it's fairly steady and clean enough. PSU is a switcher with 7a on the 5v, 1a on the -5 and 3a on the 12v.. I also run some legacy boards (non jamma) on the switcher with modded looms and -12 and -5 and blah, and they are all solid, as is my ST-V etc., so the PSU is good.
I think i'll add the second regulator in the 161 (and lose that diode) and see where that brings me..
All the games on my 161 are solid BTW.. no PCM glitching, only issues are with the usual suspects with no sound or stuck sprites which i expect are ropey dumps to start with.
Also: @GadgetUK - love the Youtube stuff, roll on my son