"crackling" distortion

[StuartR]

I have been using JamKazam for several months. Whenever I play in a session, the others describe a "crackling" distortion in my audio output. I do not hear it in my earbuds. Latency has not been a problem. My setup is:

MacBook (Retina, 12-inch, Early 2015) plugged in
MacOS Big Sur Version 11.01
Sterling Audio SL230MP Matched Pair mics
Earbuds
FocusRite Scarlett 2i2 audio interface
HyperDrive HD30F USB-C Hub
Ethernet cable -> Synology RT2600ac router -> D-Link DSL-520B ADSL2+ modem
(Would plug directly into modem, but it only has one output socket and I’d rather not unplug router)
Verizon DSL internet service

I am playing a concertina: https://youtu.be/wqwDnMXrY9Q

Other internet devices in airplane mode during JamKazam sessions.

Any suggestions/help would be appreciated. Note, fiberoptic internet service is not available in my area and I have heard that cable internet service has deteriorated.

Thank you.

Can you tell me what amount of latency is reported from your audio interface during the audio gear setup in the JK client?