Recovery problem(?)

[Guest kabooz]

I (probably) have a problem when I'm in recovery with my Desire. I can only be in recovery for about 5 minutes after that the phone reboots and start up normally and it doesn't seem to matter if it doing something or not. Right now I have flashed Amon-RA over stock ercovery but this also happened when I used clockwork with fake-flash. It usually gives me enough time to flash and nandroid backup in Amon-RA, but in clockwork it always rebooted in the middle of nandroid backups.

I have tried to search for this but haven't really found any threads about it anywhere. Is this the standard behavior or is there something strange with my device? Perhaps unroot with 2.1 RUU and reroot it?