Hi, I have been searching the internet now for 3 days and still don't have a clear idea how to downgrade my bios. I bought a second hand HP Spectre X360 15-ch075nr. It is working great except the right speaker has low volume and crackling sound and I understand this is a bios problem. Now I don't want to upgrade my bios because of all the intel microcode patches that come with it, it seems they are now even locking down cpu undervolting. So I want to try downgrading the bios but that is also locked by hp. I read that it might be possible with fpt, but on another form I saw a warning not to us the standard 083ba.bin file that comes with the hp bios packages because it deletes the UUID, Serial, DTS Key? I also see that the dump made by fpt is smaller (6mb) then the 083ba.bin file (8mb). Does anyone know how to downgrade the bios? Thanks!