Exclamation [Q] MHL HDMI Flicker/cut out

I have an AT&T Galaxy S3 running stock 4.1.2 rooted & CWM recovery. I have an MHL adapter, but it's cuts out, or shows multicolored snow quite a bit. As you may know, CM doesn't support MHL on the S3, so reverted to stock and the adapter seemed to work fine until I rooted the phone, then it started cutting out/snowing a lot.

Someone seemed to have the same issue, but one one replied. droidforums.net/forum/android-hacks-help/233660-s3-mhl-hdmi-adapter-question.html (sorry it's not a link)

Anyone have any similar issues/solutions?

Was CM10.2 before the MHL adapter, but downgraded to 4.1.2, made the mistake of updating to stock 4.3 (CFautoroot didn't work and stupid KNOX) but was able to downgrade back to 4.1.2.

Any help is greatly appreciated!