I have a new XPS15-9575 2-in-1, and the audio has started to fail. When the problem first started, the audio would work again after a restart, but now I have no audio regardless of a restart. The audio fails out of both external speakers and through the onboard speakers. I have updated the drivers and run Dell SupportAssist, and the problem persists. What other fixes should I try before asking for an exchange to a new machine?