I have this issue too.
Hardware is a different external USB DAC (not Focusrite):
$ lsusb | grep DAC Bus 005 Device 004: ID 08bb:2704 Texas Instruments PCM2704 16-bit stereo audio DAC
Symptoms: Clicking sounds. Irregular but pretty frequent, up to once a second.
It happens on kernel 5.13.0-37, but it goes away if I revert to 5.13.0-35.
I have this issue too.
Hardware is a different external USB DAC (not Focusrite):
$ lsusb | grep DAC
Bus 005 Device 004: ID 08bb:2704 Texas Instruments PCM2704 16-bit stereo audio DAC
Symptoms: Clicking sounds. Irregular but pretty frequent, up to once a second.
It happens on kernel 5.13.0-37, but it goes away if I revert to 5.13.0-35.