I paired a Bose 35 headset with my Lenovo T520 notebook (upgraded to Bluetooth 4.2). Once I switch off the headset, and later switch it on, the both do not reconnect again. The headsets reconnects to my S7 phone automatically, so does the notebook when it runs in Windows.
The workaround in CL is to disable the Bluetooth button in GNOME, toggle it back on, and once the headset shows up, to click on it and switch it back on so it says “Connected”.
I have experienced something which sounds very similar with a bluetooth mouse - I never had any difficulties pairing it initially but it would not reconnect. This happened under Gnome in both Fedora & Clear Linux.
For some reason I have found pairing using the commandline far more reliable than with the gnome applet. The aforesaid mouse, for example, always connects up now.
I haven’t done this often enough to be sure I remember, and didn’t take notes, but (in case you haven’t done this) the procedure is approximately as follows.
In a terminal:
bluetoothctl #starts up the tool
scan on
# at this point you want your bluetooth device ready for pairing - you should see its UUID appear in the terminal
pair <uuid>
connect <uuid>
trust <uuid>
quit
I’m not 100% sure I have the sequence right, but it’s along those lines