rnorth77,
This is not normal operation for the unit. I don't have any suggestions except that since you're under warranty, it might be a good idea to get it serviced.
A qualified tech would be able to better diagnose it than I would.
Keep me posted.
--HDTech
I'm having various intermittent on off problems with my new LN46A650. I've had it since December 1 2008. It has firmware 2007.0 It has turned itself off with a crackle and pop and then on again about 5 seconds later. This has happened four time over 3 months. The other day when using the remote to turn on the set the melody came on but no picture. This has only happened one time. I'm waiting until the NCAA tournament is over to get it serviced. Do you think the motherboard needs to be replaced?

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