After patching my alsa subsystem with the snd-bt-sco driver (this text on the gentoo wiki worked fine). I can finally listen to my PVR-350s Radio on my BT Headset.
btsco XX:XX:XX:XX:XX:XX and
ivtv-radio -f 95.6 -c "aplay -D plughw:Headset -f dat < %s" lets me listen Radio RaBe in something like bad mono FM quality.
My trys playing radio in stereo over A2DP with a2play failed so far. The headsets mike seems to work but i haven’t got round to testing it. Did i mention that my pvr box will also support making VoIP calls? 😉