Odd issue with 32x and Sega CD (Seems heat related)

So I noticed about 2 weeks ago, something odd on my Genesis/32x/SegaCD combo setup. Basically after the system has been on for about 30min to an hour, there appears to be a great deal of heat built up inside the Genesis itself. I actually measured this with my Fluke temp probe and the ambient air temp in the Genesis reaches about 112°F around the AV port. That seems excessively hot to me but perhaps not?

The specific issue this seems to cause is that video overlayed from the SegaCD itself will show up with a snowy like pattern on the screen. But only from the video from the SegaCD itself. I've posted a link below showing the effect. Basically at first when you power everything on and look at the SegaCD bios screen everything appears normal. Then after some time, it will produce a horrible graphics corruption issue as is shown second in the video. Then, if I remove the 32x completely from the system the video is normal again.

Now I have found out that the 32x appears to be the cause. Not sure why, but it is. In the video, the actual video you see on my TV is using the AV out port on the Genesis itself and not from the 32x. However the same results appear from the 32x AV port as well. So the video corruption isn't from the 32x encoder but somehow from a combination of the 32x being attached along with the SegaCD.

So far this graphics corruption isn't actually seen in games with the exception of those using FMV. As an example notice in the sega CD bios screen the graphics issue is only within the window frame of the bouncing Sega CD logo and doesn't affect the text graphics outside that? When I play Sonic CD with the system warmed up and doing this, the graphics glitches are present within the window showing the Sonic CD cartoon intro, but not outside the frame of the intro and do not appear at all within the actual game. Even on the bonus stages where the rotation and scaling effects are being used do not show this issue. Normal cart games are fine as well and if I remove the 32x, the Genesis doesn't seem to get as warm and of course the graphics issue from the Sega CD doesn't appear at all.

Has anyone seen anything like this before? I'm trying to get ahold of another 32x base unit for cheap that works to see if it is the 32x actually causing the issue or something within my genesis somehow.

https://youtu.be/LMS6E46EhUo

I hadn't updated this, but with some further testing and just generally more questions than answers, I've at least got something in place that works for now.

So in further testing I discovered that the 32x isn't the cause, but it is the trigger. So if I leave the Genesis up and running with a game loaded in but without the 32x attached, then the entire system gets as hot as about 112° - 115°F ambient temp within the case near the the rear expansion port. The 68k will get up to about 150°F. Even plugged into the SegaCD, as long as the 32x isn't attached then the SegaCD bios screen will appear normal.

Now if you plug in the 32x with power plugged into it and turn the Genesis on once it is at this temp, then you will see the video snow pattern as seen in my video. However, if you then unplug the 32x while still leaving it connected into the Genesis, the snow pattern will immediately go away and you have a clear SegaCD bios picture again!?

The 32x doesn't even have to be hot. Just get the Genesis up to temp. Turn off the genesis and quickly pop in the 32x and plug it in. Turn on the Genesis with the SegaCD attached and you have the snow pattern on the screen. Yank out the power from the 32x and the snow pattern immediately clears up.

Something with the 32x power being plugged in is causing this issue. I also tried different power supplies I have on hand with no change. I came up with a theory late last week.

Thinking the standard 7805c VRs seem to be the source of most of the hear in the system and they appear to be getting much hotter than I would deem normal, I ordered some new 78S05CV VRs to replace them with. These are more modern +5 VR with a 2amp output rating on them. My theory was that if the entire system is drawing off more current than the original 7805s were expected to pull, then putting in some new ones with a higher amp rating should mean the newer ones run cooler.

And that appears to be the case. After installing the two new 78S05CV VRs, I repeated the above experiments and had the Genesis up and running with the 32x plugged in and running Star Cruiser in demo mode. Even after 4 hours of this..the SegaCD bios screen still comes up normal and no snow pattern to be found. I have to assume that the s-video mod, plus the added YM3438 plus the 32x is causing some issue combined and the old VRs just couldn't quite generate a clean enough power source once at temp.