I have the following BT headset:

Requesting information ...
         BD Address:  00:09:DD:30:65:2B
         Device Name: BT Headset
         LMP Version: 1.1 (0x1) LMP Subversion: 0x434
         Manufacturer: Cambridge Silicon Radio (10)
         Features: 0xfc 0xff 0x0f 0x00 0x00 0x00 0x00 0x00
                 <encryption> <slot offset> <timing accuracy> <role switch>
                 <hold mode> <sniff mode> <park state> <RSSI> <channel 
quality>
                 <SCO link> <HV2 packets> <HV3 packets> <u-law log> 
<A-law log>
                 <CVSD> <paging scheme> <power control> <transparent SCO>


I managed to compile snd-bt-sco.ko and btsco

./btsco -v 00:09:DD:30:65:2B
btsco v0.4c
Device is 1:0
Voice setting: 0x0060
RFCOMM channel 1 connected
^^
when playing something with aplay -D plughw:Headset sound.wav btsco says

speaker volume: 12 mic volume: 1
i/o needed: connecting sco...
connected SCO channel
Done setting sco fd
recieved AT+VGS=12
Sending up speaker change 12
^^
I hear increased noise but no sound. When aborting btsco says:

speaker volume: 12 mic volume: 1
driver is not in use
disconnected SCO channel
^^

from dmesg I get:
snd-bt-sco: playback_open
snd-bt-sco: prepare ok bps: 16000 size: 8000 count: 2000
snd-bt-sco: playback_trigger 1
snd-bt-sco: setting playback to bspcm
snd-bt-sco: playback_trigger 0
snd-bt-sco: setting playback to NULL
snd-bt-sco: Disposing of previous socket count 3
snd-bt-sco: file_count is 2 (expected 3)
^^

I found a posting on bluez-users pointing to 
http://sourceforge.net/mailarchive/message.php?msg_id=11431438
(http://sourceforge.net/mailarchive/message.php?msg_id=11487825)
but this did not work for me. Anyone having any hints?

regards
roland lezuo