Hi Kelly,
I have the tomy walkabout ones ( i think), ours dont have the temp on it, but have had similar probl;ems but for us it kept bleeping manically at me at random points though night and switched its self off. It does do this when the monitor is down stairs. i have come to the conclusion the parent and child monitors are too close when it is upstaiirs ( despite there being a wall between us lol) so now i dont use it in bed i just go and check on him when i wake. x