Downgrade to kernel 5.4.0 because kernel 5.8.45 doesn't like my bluetooth controller

I had no bluetooth issues with kernel 5.4.XX until I updated to kernel 5.8.0. I can't select 5.4.XX from Grub, is not there.

If I type dpkg --list | grep linux-image | grep ^ii on the terminal that's the result:

ii linux-image-5.8.0-38-generic 5.8.0-38.43~20.04.1 amd64 Signed kernel image generic
ii linux-image-5.8.0-40-generic 5.8.0-40.45~20.04.1 amd64 Signed kernel image generic
ii linux-image-generic-hwe-20.04 5.8.0.40.45~20.04.25 amd64 Generic Linux kernel image

How can I downgrade to the latest kernel 5.4.xx again?

1 Answer

Run in a terminal

sudo apt install linux-generic

This will install the latest 5.4 Ubuntu kernel.

Then reboot and select a 5.4 kernel in advanced options of grub menu.

Then remove the 5.8 kernel packages including headers, modules and modules-extra