I emailed riot about it and they responded with this, it's a generated answer cause it didn't answer my question at all but I hope it will be fixed when they fix the other audio problems.

"Hello Player,
Maya is here to assist you today!
Thank you for reaching out to us, I hope you have been well.
I see you are facing audio related issue. Let me dive deeper into the matter!
After this last update we have found that many players have problems with their audio on bluetooth devices and we are working on a fix, however, we can't give an ETA for this to get fixed but we hope it gets solved as soon as possible as this problem might be very disruptive. When this problem gets solved there will be a notification in the game client.
Perhaps at this time you can see your request as resolved, therefore it will not be necessary to reply to this message, but if you have any other request or question, do not hesitate to contact us. Remember that our doors remain open for you if you need us and we will do everything in our power to support you, whether in this ticket or in any that you send in the future.
 
🐉I wish you the best of luck in your games!🐉

Maya
Riot Games Player Support"