Bluez 5, A2DP headphones

I'm having trouble connecting to my headphones after upgrading from Bluez 4 to Bluez 5 with a few more people.
Link to Gentoo Bugzilla: https://bugs.gentoo.org/show_bug.cgi?id=499908

Summary:
I'm not using PulseAudio and this is the error from system journal:

2月 09 15:01:54 melforce bluetoothd[12825]: a2dp-sink profile connect failed for 00:02:3C:31:96:12: Protocol not available

It appears when I try to connect to it from bluedevil (KDE's Bluetooth stack) or when mplayer2 tries to open the ALSA device.

Do you have any clues?