I have a pair of ERA300s. Works great for streaming. However, when turntable is plugged in it usually only plays through the speaker with Line in. After says 15 mins the other speaker will kick in. I have swapped cables and left and right inputs from the turntable and get the same result. Plugging turntable into other hi-fi system does not suffer same results so I am thinking this is related to the Line in on the Sonos.
Best answer by GuitarSuperstarView original
Try setting the Audio Delay under the Line-In settings to MAX. You can also try setting the Audio Compression setting in the Sonos app to Compressed.