You're a pro player with a GTX 970? "Member Since: Monday" Cool story. Here's one that can be replicated. This has the same issue as from the 445.75 driver. HDMI audio. The GPU does not see the device, in this case a Samsung 4K TV as being connected when resuming from sleep. The Sound control panel shows it as disconnected. You cannot reset it within Windows, a reboot restores function. A temp fix is to remove the existing Nvida HD audio driver via device manager an let Windows install an earlier MS version. MK1 Calibrated eyeball, of course.