Same issue as everyone on this string......with a twist. OTA channels won't play when the 2 TB expansion drive is plugged into the Tablo USB. With the device unplugged, everything works as it should. The audio settings work around made no difference in my environment.
Two Roku's and a Tablo. All devices are two weeks old and on the latest software. Expansion device is a Seagate 2TB disk drive, USB interface.