Default Problem: Nokia HDW-3 BT-headset - HTC PC3300


I'm using the HTC P3300 PDA and I would like to use it with my older Nokia HDW-3 bluetooth headset. Pairing is succesfull and I can use the headset without a problem. But when I don't use the phone/headset for (example) 30 minutes and I would like to call someone, the P3300 displays a headset symbol, but I can't hear anything through the HDW-3. Turning off the headset and turning it on again will fix the problem...only for a short time. It looks like both devices can connect and work correctly, but after a standby time it doens't work anymore without a headset reset.

Does some recognize this problem? When pairing both, only the "handsfree" profile is available. (No headset profile?). The HDW-3 has always worked perfectly with my Nokia 6600 till last week (before upgrading to the HTC P3300). So I don't think it is defect. The P3300 works great with my Parrot 3100LCD bluetooth carkit, so it is unlikely that bluetooth on the P3300 isn't working correctly. What to do? :)

Thanks in advance for any reply.