v551 shutting down after 5 minute call?

I bought 2 v551's . (one for me, one for my lady) hers cuts off after 4.75 to 5.00 minutes of talking. mine does not CINGULAR says "not our problem" any body have any ideas?
ALSO: I'm looking for a good drop in (desk top) charger. ALL ideas will be appreciated!

Dave

Dave,

here is the scoop. Motorola released a batch of V551s that are defective. I had one where the battery would only last two days WITHOUT even using the phone. I found out from a Cingular rep (not supposed to tell me) about the phones. Call 1-800-801-1101 and tell them you phone is defective and get another phone. I am guessing that the phones are new. They have a one year warranty from Motorola

cant remember my mums phone model of the top of my head but hers does exactly the same after 10 minutes and she already took it in for a dodgy screen