No Sound/Only Picture

Worked fine in the moring then starting getting this issue in the afternoon. Picture in SD and HD is perfect but no sound on any channel. Checked TV settings and MUTE is off and am able to get sound out of other sources (DVD, XBOX360, etc) except the DirecTV HDDVR receiver connected via HDMI. Tried the resetting steps by unplugging it and by the reset button on the rear of the box but nothing. Any other ideas before I call for DirecTV to come out and look at it?? Just for reference our weather here has been overcast/cloudy for the past several days, not sure if that has anything to do with my issue.