I have the very same problem using the same distro (Ubuntu 18.04, 64-bit) on Dell Latitude E5400 laptop. Disabling BT from BIOS or removing the aforementioned rule solves the problem but leaves BT unusable.
I have the very same problem using the same distro (Ubuntu 18.04, 64-bit) on Dell Latitude E5400 laptop. Disabling BT from BIOS or removing the aforementioned rule solves the problem but leaves BT unusable.