Comment # 1 on bug 965538 from Takashi Iwai

It's hard to judge only from the given information.  Usually the endless noise
means the interrupt handling going wrong, and it's often a BIOS- or
ACPI-related problem.

In anyway, please run alsa-info.sh with --no-upload option before and after the
issue happening.  Also, give dmesg output after the problem happens.

To clarify: you tested both built-in audio and HDMI/DP audio, and both went
bad?