Dino451 @ macrumors says:
Dino451 @ macrumors says: Oct 1, 2010, 09:05 PM
"I had the same problem upgrading to ios 4.1 and jail breaking on my 2G iPod touch. I have a non-apple cable that works fine on ios 4.0 and jail broken. I upgraded to ios 4.1 and to my surprise my cable did not output to my TV with 4.1/jailbroken. I did many tests and found out that the problem is Cydia/using snow breeze 2.0. I tested a fresh install of 4.1 and it worked fine. I tested it with my backup restored, it worked fine. I tested it with 4.1 jailbroken/restored from backup with Cydia installed but not configured for the first time, it worked fine. After the first time Cydia configures itself for the first time, tv out is disabled. I did this twice to make sure, starting cydia for the first time disabled tv out. I have reluctantly downgraded to 4.0 just for tv out because I use it more than I thought. waiting for another jailbreak(PC) to upgrade and get the features I want. I also tried those cydia apps with 4.1 and nothing worked"
It sounds like an update to jailbreak/cydia install or config could fix this. If anyone hears of a solution please post here. I used greenpois0n rc3.