FC Twin plays NES but not SNES

[col_sandurz]

I purchased an FC Twin console over a year ago.  At the time I tried an NES game to check functionality and it worked.  Recently I bought a couple SNES games (Return of the Jedi and Star Trek TNG) and they did display video on the FC Twin.  I can hear the music but no video (the screen blanks as if the video were not connected, not simply black screen).

So, I began troubleshooting.  I tried playing the SNES games both with and without an NES game plugged in, no difference.  I started pulling connections and noticed something strange.  When the FC is plugged into my receiver (but not my TV) and playing an NES game, I will lose the video if I disconnect the audio cables.  Yes, the video cable is still connected, but it's as if the video were not (i.e. the screen blanks as if the video were not connected).  I opened up the system figuring it may be a connection trouble.  I did not see anything, but the ribbon cables connecting the logic boards are covered in hot-glue at the connection points.  I tried running a separate ground cable from the SNES board to the output/power board, no results. 

I also noticed the power supply is 9V 850mA, which is the same rating the original NES states on the bottom of the console (I have one), but the NES uses a 10V 1.2A power supply.  Thinking maybe the system may not have adequate power I utilized a Sega power supply that outputs 10V 1.2A with the same connector and polarity as the FC supply.  The system ran... the same as before, no video with SNES games.

So my thoughts are now these: the system might still not be getting enough power and/or the SNES portion is not properly grounded.  However, the controllers, which plug into the SNES board, do work.  I'm wondering now if it has to do with the video chip or if it is related to the thin ribbon cables connecting the logic boards.  Seeing all the hot glue inside the case (it is also securing the dual LEDs) and the fact that the boards look as if they were wiped not-so-clean of some spilled liquid, I seriously do not doubt it has build quality issues.  Does anyone have any suggestions or ideas that may help me salvage this thing?  I know others have had this issue (see the 8th post here http://nfggames.com/forum2/index.php?topic=2521.0 ) but I have not seen any answers.

Thanks all, Col Sandurz