Tried the online support chat.
You have been connected to Rob.
Rob: Hi Sharon, thank you for contacting HTC Support, I am looking in to your query now.
Rob: Have you tried another SIM card?
Sharon: thanks
Sharon: yes same problem
Rob: Could you provide me with the serial number of the mobile phone?
Sharon: signal stays at around -106dBm
Rob: OK have you tried changing the signal?
Sharon: yes, still drops after a while
Rob: Have you tried a hard reset?
Sharon: yes
Rob: Can only book the phone into repair if you wish to proceed?
Sharon: thing is, i've done some research online and on the HTC forums, ppl appear to be having the same problems. With repair still not solving the problem
Sharon:
http://androidforums.com/htc-desire-s/396171-signal-drops-completely-htc-desire-s-8.html
Rob: Page not found. There could be a broken antenna, the sms arriving late is only a known issue with the Desire S and 2.3
Sharon: ah ok. they have narrowed it down to a software update.. and it appear mine seems to be the same. The phone has been fine, until around 2 or 3 weeks ago
Rob: This hasn't been a issue with the standard desire
Rob: Your phone would need to go into repair to resolve this
Sharon: ok thanks for your help
Perhaps I should just book it in :s Getting quite annoyed now as missed call from a job agency. Luckily they left a vmail but not many ppl do!