Thunderbolt HDMI HDTV issues

Ok, so I have the latest model 13" macbook air with Lion, and when I connect it to my 720p hd tv to watch movies, the display/sound fades in and out. i.e. it works notmally for 10-30 seconds, then blacks out/mutes the audio (coming through HDMI). I am using the griffin adapter. Same issue occurs at different resolutions.

The same adapter/computer works fine on my 720p projector (no flickering).

The same adapter/ HDMI cable(tried 2)/TV works fine with my pre-thunderbolt mac book pro.

Same issue with or without audio running through HDMI.

HELP!!!!