May also be an issue where R/L sync is switched from PLC to wifi for some reason (and back when you do the input switch routine). Like Snoopy says, sounds like a bug. Can you try connecting both speakers to your network with ethernet cable? I believe ethernet will be preferred over wifi and PLC for sync.
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Devialetless!
Roon or LMS/brutefirDRC on DietPi_x86_64
piCorePlayer/ISORegen/HeadStreamer/Yamaha HP-1
250 Pro CI, MicroRendu, Mutec MC-3+USB
Devialetless!
Roon or LMS/brutefirDRC on DietPi_x86_64
piCorePlayer/ISORegen/HeadStreamer/Yamaha HP-1
250 Pro CI, MicroRendu, Mutec MC-3+USB

