I've been living with this for years and editing my way round it but I recently signed up to SOS so I thought I would ask around the forum.
When recording to Logic Pro X via Behringer UMC22 USB interface on my Macbook Pro (Retina, 13-inch, Early 2015, Big Sur) I sporadically get a click/pop sound. The sound is definitely recorded as I can hear it during playback. When I zoom in to the click/s I can see something that looks like the waveform was recording fine but then a small square chunk of it was taken and flipped/inverted around the zero line.
This shows what I mean:

When does this happen?
It is sporadic, as in I can go days without hearing it then get 3 or four on a track then in the same project I won't hear it again for days. Sometimes it happens multiple times in the same sitting.
Things I have tried, that seem to have not had any effect:
Macbook running on battery/plugged in to AC power.
USB cable replaced with half a dozen different cables.
Different USB interface tried (Behringer UCA222)
Disabled WiFi on the Macbook
Disabled Bluetooth
Disabled WiFi and Bluetooth
Quit Dropbox (runs on startup)
Various sources (guitar, synth, radio)
Dropped buffer setting from my usual (256) to 512 and 1024
I've Googled everything I can think of searching for
I've read numerous articles on clicks and pops in SOS which lead to me investigating mains appliances as a possible cause:
- Looked at timings of heating (boiler)
- disabled boiler and thermostat
- Tried shutting the fridge freezer off
- Switched off WiFi router
But still it persists...
Can anyone offer any ideas please?
thanks so much, I live in hope!
Christoph