Simple Sega Gen Model 1 A/V adapter mod. (almost)

[humanman42]

So I got this Sega Gen a long time ago. I lost the A/V adapter a while ago. So I decided to mod it to accept a 8th" to a/v cord.

http://imgur.com/a/AuNKm#ONTto" onclick="window.open(this.href);return false;

So the audio and video work. For some reason the audio house a loud hum. Any idea why? I checked the solder points and those are not touching. Any ideas?

Also, I have never seen anyone do this clean of an a/v mod. Used the existing hole in the back which was almost big enough. I did this on a model 2 for a friend with stereo audio and it worked fine.

Thanks for any help.

casey