Hi,
if I do

> modprobe snd_bt_sco
> esdctl stop
> hciconfig hci0 voice 0x0060
> btsco <address_of_my_headset>
> aplay -B 1000000 -D plughw:Headset <some wav file>

I can't hear anything else than a bip in my headset,
that is properly paired (I checked with 'hcitool con')
'dmesg' gives me what follows: 

Bluetooth: Core ver 2.7
NET: Registered protocol family 31
Bluetooth: HCI device and connection manager initialized
Bluetooth: HCI socket layer initialized
Bluetooth: L2CAP ver 2.7
Bluetooth: L2CAP socket layer initialized
Bluetooth: RFCOMM ver 1.5
Bluetooth: RFCOMM socket layer initialized
Bluetooth: RFCOMM TTY layer initialized
eth0: link up, 100Mbps, full-duplex, lpa 0x41E1
eth0: link up, 100Mbps, full-duplex, lpa 0x41E1
eth0: no IPv6 routers present
snd-bt-sco revision 1.6 $
snd-bt-sco: snd-bt-scod thread starting
usb 1-1: new full speed USB device using ohci_hcd and
address 3
Bluetooth: HCI USB driver ver 2.8
usbcore: registered new driver hci_usb
usb 1-1: USB disconnect, address 3
usb 1-1: new full speed USB device using ohci_hcd and
address 4
snd-bt-sco: playback_open
Bluetooth: SCO (Voice Link) ver 0.4
Bluetooth: SCO socket layer initialized
snd-bt-sco: prepare ok bps: 16000 size: 16000 count: 4000
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 1 (expected 3)
hci_scodata_packet: hci0 SCO packet for unknown
connection handle 256
hci_scodata_packet: hci0 SCO packet for unknown
connection handle 256
hci_scodata_packet: hci0 SCO packet for unknown
connection handle 256
snd-bt-sco: playback_open
snd-bt-sco: prepare ok bps: 16000 size: 16000 count: 4000
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: playback_open
snd-bt-sco: prepare ok bps: 16000 size: 16000 count: 4000
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: playback_open
snd-bt-sco: prepare ok bps: 16000 size: 16000 count: 4000
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

moreover these are possibly useful infos:

> hciconfig -a
hci0: Type: USB
BD Address: 00:11:F6:01:5A:78 ACL MTU: 120:20 SCO MTU:
64:0
UP RUNNING PSCAN ISCAN 
RX bytes:583 acl:12 sco:0 events:45 errors:0
TX bytes:610 acl:12 sco:0 commands:21 errors:0
Features: 0xff 0xff 0x05 0x38 0x18 0x18 0x00 0x00
Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3 
Link policy: RSWITCH HOLD SNIFF PARK 
Link mode: SLAVE ACCEPT 
Name: 'piro-0'
Class: 0x7e0100
Service Classes: Networking, Rendering, Capturing
Device Class: Computer, Uncategorized
HCI Ver: 1.2 (0x2) HCI Rev: 0x0 LMP Ver: 1.2 (0x2) LMP
Subver: 0x757
Manufacturer: Silicon Wave (11)

> hciconfig hci0 revision
hci0: Type: USB
BD Address: 00:11:F6:01:5A:78 ACL MTU: 120:20 SCO MTU:
64:0
Unsupported manufacturer

> hcitool info 00:07:A4:2D:9E:48
Requesting information ...
BD Address: 00:07:A4:2D:9E:48
Device Name: Motorola HS820
LMP Version: 1.2 (0x2) LMP Subversion: 0x525
Manufacturer: Cambridge Silicon Radio (10)
Features: 0xff 0xff 0x0b 0x00 0x08 0x08 0x00 0x00
<3-slot packets> <5-slot packets> <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> 
<transparent SCO> <AFH cap. slave> <AFH cap. master>

> btsco -v
btsco v0.4a
Device is 1:0

btsco bluetooth audio handler

> uname -a
Linux piro 2.6.12-rc1 #1 Mon Apr 25 11:15:24 CEST 2005
i686 GNU/Linux

and the output of hcidump -X is attached

best regards
          
-- 
Cristiano De Michele, Ph.D.          E-mail: cristiano.demichele@phys.uniroma1.it
Department of Physics                Tel.  : +390649913435
University of Rome  "La Sapienza"    Fax   : +39064463158
Piazzale Aldo Moro 2
I-00185 Roma - Italy    
------
"Shoot for the moon. Even if you miss, you'll land among the stars."