F3000 won't ring

I bought a UTstarcom F3000 WiFi phone, and I can get it to register to my Asterisk box. I can also place calls from the phone without trouble. I cannot however get the phone to ring. It remains silent even when the Asterisk CLI says that the phone is ringing. I have the phone itself set to ring… do not disturb is disabled, a ringtone is set and it is not set to block anonymous calls. I see “Invite” entries in the phone’s local log but no ring.

I had a Linksys WIP300 using the same sip.conf entry and it did ring when called. Can anyone suggest something, or should I assume that the phone is broken. Despite this phone being advertised as New on VOIPsupply’s Ebay auction, when it arrived it had some guy’s sip account info entered into it. I wonder if they’re selling returns on Ebay as new.