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, ROCK/Audiolense XO/Music on NAS/EtherRegen/RoPieee/USPCB/ISORegen/USPCB/Sound Devices USBPre2/Tannoy GOLD 8
250 Pro CI, MicroRendu(1.4), Mutec MC-3+USB
Devialetless!
Roon, ROCK/Audiolense XO/Music on NAS/EtherRegen/RoPieee/USPCB/ISORegen/USPCB/Sound Devices USBPre2/Tannoy GOLD 8
250 Pro CI, MicroRendu(1.4), Mutec MC-3+USB