HTC Amaze :: It Loses Service In City Then Battery Drains

Firstly, I want to state how extremely impressed I am with the Amaze, both in its construction quality, its wonderful screen, very good normal use battery life, and its generally sophisticated and flawless operation. I am very satisfied with my choice.One of the very few problems I have had, is that occasionally, whilst still in city zones with good service, the phone will lose cellular signal, then run the battery flat much more rapidly than usual whilst trying to re-establish service. My first indication of the problem is when I find the phone dead, when it should still have say 80% charge. Remedy is to switch off & pull battery
Has anyone had similar experience?I recommend an audible warning when cellular service is lost, so that user can take remedial action before battery goes flat, and so that important incoming calls are not lost. This should be an easily programmable feature for next update.