UR-RT4 main output left channel stopped working

Hey all, very recently my UR-RT4 has stopped playing back out of the left main output channel. The control panel mixer meters show audio output, and I’ve tried switching the cables and am satisfied it isn’t an issue with the cables or speaker. I’ve tried installing new driver, and have also tried the interface on a seperate laptop. Unfortunately the problem persits for all playback. I’m using Windows 10. Any advice very welcome! Thanks so much in advance.