I have the following Problem: I have a headset which I want to connect via bluetooth - No problem (A2DP is just fine). But if I try to switch to the HSP/HFP profile I can't do this. It results in the 'Can not switch to HSP/HFP' error.
I have searched and tried many solutions but I can not make it work (I connected the Headphones via terminal, blueman, pavucontrol and so on. I even installed different linux distros hoping to use my Headset there). My Beyerdynamic Headset works fine on Windows - with the same bluetooth dongle, no need to say. Skype and discord calls are no problem there.
Here are the technical details:
0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode) on Ubuntu 18.04 with 4.15.0-91-generic Kernel (also other OS like: Elementary 19.1)
Can anybody help me with that? I really like it to work on ubuntu but if I can not use my headset microphone I have to switch OS. :( Are there any experiences with this cambridge adapter? It seems to be the reason for troubles. Is there any newer/better firmware or drivers for this? It also seems to be no ubuntu error because connecting the headset on my ubuntu laptop and using HSP/HFP there works just fine. Any help, assumptions, tips and hints appreciated! Thank you!
EDIT:
Due to the answer of pbhj: I tried switching via the Graphical User Interface 1. In the Os settings 2. In Pavucontrol and also in commandline. The error messages where displayed there.
EDIT #2:
In the meantime I have found this thread. It looks like there is simply no solution for this problem. The bluetooth adapter is really fine if you just need audio output A2DP, because it is low cost. But no recommodation for headphone usage on Linux (On windows it works absolutely fine). :/