08-05-2011 10:33 PM
I have a new T420s (4173-CTO) with integrated Bluetooth 3.0 (Win 7 Home Prem.) that I have paired with a Belkin Music Receiver (F8Z492au) that is plugged into an auxiliary port of a stereo amplifier (RCA). But I can't get any music to come out of the loungeroom speakers. If I plug the laptop directly into the RCA ports of the amp there is no problem.
I believe I have paired or connected to the Belkin device successfully--although it is called a "Bluetooth headset" rather than "Stereo Audio" or something more appropriate.
Do I need to get a Stereo Audio profile displayed in the Sound->Playback tab rather than the "Bluetooth Hands free Audio" of the headset profile? Perhaps do something extra to enable my ThinkPad for 'A2DP stereo' (?), so I can output to my stereo speakers through the Belkin receiver?
Under Headphones Properties the Advanced tab shows default sample rate & bit depth as "2 channel, 16 bit 48000Hz (DVD quality)".
Under Bluetooth Settings, Hardware tab I have:
'Microsoft Bluetooth Enumerator' with Driver : 6.1.17601.17607; and
'ThinkPad Bluetooth 3.0' with Driver : 188.8.131.521
Under Devices & Printers, Belkin device (G13) Properties, Hardware, Properties, I have:
'Bluetooth AV' with Driver : 184.108.40.2060
The option to update these drivers in the above tabs are greyed out.
I see from Programs & Features that "ThinkPad Bluetooth with Enhanced Data Rate Software" (Broadcom) is installed with Driver version 220.127.116.110.
I have found the following related posts but they don't really help me (tried Win 7 equivalent of number 1):
# JamesZ advice (device doesnt show as ".. Stereo Audio" anywhere)
Thanks for your help
09-26-2011 02:29 PM
Similar problem with my Nokia BH-905 headphones. On my Dell with the Toshiba BT stack, I had 2 seperate devices/profiles showup for the Nokia BH-905: a bluetooth headset and an A2DP Headphones. In my ThinkPad T420 I just have a bluetooth headset listed for the Nokia BH-905. While the services for teh BT headset show both "Bluetooth AV" and "Bluetooth Headset" and the audio settings in Windows 7 for the BT headset are set to DVD quality, the sound quality from the Nokia BH-905 is significantly poorer than when using them with my Dell. It sounds as if the audio is being compressed at a very low bit rate for transmission via Bluetooth to the headphones. Is there a way to verify that the profile for my Nokia BH-905, specifically the "Bluetooth AV" service is, in fact, and A2DP profile? Any help would be appreciated.
10-04-2011 01:31 PM
Did some additional research, testing, and configurations. Final conclusion: the T420s bluetooth audio is just crap.
Definitely not the headphones, because they work fine with the old laptop, and even better with my iPhone. Tried with a different pair of bluetooh headphones as well. No configuration yields better results than another, that I can tell. Either the T420s bluetooth drivers don't offer a true AD2P profile, or the one that is offered just doesn't sound good. I guess I will be streaming music with my iPhone from now on. Not going to be good for my battery life, though