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Can BlueZ use AAC codec with A2DP?

Question asked by Takashi Kashiwagi on May 8, 2019
Latest reply on May 23, 2019 by Takashi Kashiwagi

Hi Community.

 

I have using 8MMINILPD4-EVK with 4.14.78-sumo.

 

I tryed pairing with iPhone via A2DP and btusb, it's OK. but codec is still SBC. I want to use AAC.

I think it would be possible to change the BlueZ settings, but does anyone know the correct settings?

 

The connection log is as follows. BlueZ seems to recognize AAC, but it looks like it is going to connect with SBC.

root@imx8mmevk:~# sudo hcidump avdtp
HCI sniffer - Bluetooth packet analyzer ver 5.49
device: hci0 snap_len: 1500 filter: 0x400
< AVDTP(s): Discover cmd: transaction 3 nsp 0x00
> AVDTP(s): Discover rsp: transaction 3 nsp 0x00
ACP SEID 1 - Audio Source
ACP SEID 2 - Audio Source
ACP SEID 3 - Audio Source
ACP SEID 4 - Audio Source
ACP SEID 5 - Audio Source
ACP SEID 6 - Audio Source
< AVDTP(s): All Capabilities cmd: transaction 4 nsp 0x00
ACP SEID 1
> AVDTP(s): All Capabilities rsp: transaction 4 nsp 0x00
Media Transport
Media Codec - SBC
44.1kHz
JointStereo
16 Blocks
8 Subbands
Loudness
Bitpool Range 2-250
Delay Reporting
< AVDTP(s): All Capabilities cmd: transaction 5 nsp 0x00
ACP SEID 2
> AVDTP(s): All Capabilities rsp: transaction 5 nsp 0x00
Media Transport
Media Codec - SBC
44.1kHz
JointStereo
16 Blocks
8 Subbands
Loudness
Bitpool Range 2-250
Delay Reporting
< AVDTP(s): All Capabilities cmd: transaction 6 nsp 0x00
ACP SEID 3
> AVDTP(s): All Capabilities rsp: transaction 6 nsp 0x00
Media Transport
Media Codec - MPEG-2,4 AAC
MPEG-2 AAC LC
44.1kHz
2 Channels
256000bps VBR
Delay Reporting
< AVDTP(s): All Capabilities cmd: transaction 7 nsp 0x00
ACP SEID 4
> AVDTP(s): All Capabilities rsp: transaction 7 nsp 0x00
Media Transport
Media Codec - MPEG-2,4 AAC
MPEG-2 AAC LC
44.1kHz
2 Channels
256000bps VBR
Delay Reporting
< AVDTP(s): All Capabilities cmd: transaction 8 nsp 0x00
ACP SEID 5
> AVDTP(s): All Capabilities rsp: transaction 8 nsp 0x00
Media Transport
Media Codec - non-A2DP (Unknown)
00 80 00 84 00 84 E2 00
Delay Reporting
< AVDTP(s): All Capabilities cmd: transaction 9 nsp 0x00
ACP SEID 6
> AVDTP(s): All Capabilities rsp: transaction 9 nsp 0x00
Media Transport
Media Codec - non-A2DP (Unknown)
00 80 00 84 00 84 E2 00
Delay Reporting
< AVDTP(s): Set config cmd: transaction 10 nsp 0x00
ACP SEID 1 - INT SEID 4
Media Transport
Media Codec - SBC
44.1kHz
JointStereo
16 Blocks
8 Subbands
Loudness
Bitpool Range 2-53
> AVDTP(s): Set config rsp: transaction 10 nsp 0x00
< AVDTP(s): Open cmd: transaction 11 nsp 0x00
ACP SEID 1
> AVDTP(s): Open rsp: transaction 11 nsp 0x00

 

Best Regards,

T.Kashiwagi

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