2 years later, I still have the same issue.
In Raspbian, using the built-in Bluetooth controller:
- Connect a BT mouse
- Connect a BT keyboard
- Turn on the built-in Wifi and connect to a network
The mouse and keyboard should work properly, as anyone would expect.
- Mouse and keyboard will work intermittently and erratically.
- Mouse and keyboard devices will will disconnect (BT led will stop blinking) seconds after the user stops using them. They will connect againg (wake up) eventually and unpredictably.
Interestingly enough, the wrong behavior disappears as soon as the Wifi controller is turned off.
How can I fix this?