Best answer by Ken_Griffiths
LED Lights on Sonos Products.
I would perhaps choose to Submit a Sonos System Diagnostic immediately after the next dropout of the PlayBar and post the reference here. Then contact Sonos Customer Care via the link below and ask them to look at the Diagnostic report to see if they can see any possible reason for this happening.
Contact Sonos Customer Care/Twitter (24/7) etc.
Hope that helps.?