Genesis model 1 with a lifted pin on the CPU?

I just bought a Genesis model 1 VA6 that I wanted to mod with s-video. When I plugged it in it had really bad video that would fade out over time. I opened it up and saw that someone had lifted pin 6 on the Motorola MC68000P8 chip and attached a resistor. Why would someone do that? Is this some some of mod gone bad?

http://i.imgur.com/SGT7deT.jpg

Thanks for any info.

Edit: I did an av mod to it and I have strong(er) video now, but almost inaudible audio with a loud hum. The video has horizontal scrolling lines and a flicker. I think I might need to recap the whole system. Any other ideas?

 

its from factory, they're "all" like that.

 

Really? Weird, ok. I'll have to find another cause for the crappy video. Thanks a ton.

 

Ahem: http://console5.com/store/kits/game-console-cap-kits/game-console-cap-kits-sega.html

 

iirc my model 1 Megadrive is the same

 

Yep, that's where I always get my cap kits

 

The 220ohm resistor on the MC68000 pin 6 (/AS) is meant to prevent the console from crashing under certain circumstances. If it has that factory patch, it's using a FH0001 chip as VDP instead of the "classic" YM7101 VDP. Apparently sometime around 1992 Yamaha re-designed the VDP chip and it had that errata. MD consoles with a Hitachi 68000 and the FH0001 VDP will not have the resistor (also there's a trace cut under the 68000 and a black jumper at the other side of the board).

Without these "erratas" fixed the console will crash a lot.