The audio cuts out at randomly when using the optical input with my TV, what can I do?

When using the optical input of the D1 DAC or the HD6 speakers, you'll need to make sure your TV's audio output is set to PCM (not Dolby, DTS, or 5.1/surround).  Special hardware is needed to process Dolby audio signals.  If your TV is set to Dolby, it's likely you'll hear some audio but it will be intermittent in nature with dropouts.  Once the output is set to PCM, this should resolve the issue.  Check with your TV manufacturer for directions on how to make this adjustment.