Hi, Marcel BlueZ Wiki site the following is written. The Sony Ericsson HBH-DS970 and HBH-DS980 are not compliant with the bluetooth spec. Currently, they do not work well with bluez, but a workaround is in development. http://wiki.bluez.org/wiki/MotorolaHBHDS9x0 As far as I know, BlueZ wiki site was used for BlueZ 3.xx However even if I use with BlueZ 4.44(latest), they do not work well.. If you know the workaround your site mentioned , could you explain that for me? What I found is below. After HFP RFCOMM connection and 10 seconds later, A2DP session is so slow.. MTU is so small and their respond is too late. I guess that in case of another phone, it's no problem because their connections(HFP,A2DP)are made simultaneously. However in BlueZ case HFP,A2DP connection is separated. As a result it takes more time to connect stereo Headset A2DP service than another device. Regards Chanyeol -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html