I'm trying to help a client change audio settings on a Roku 4 over the phone and I haven't been able to find an actual manual on the unit itself, only a cursory setup guide.

The components we have (nope, no new components will go into this system) are a compromise, and sound sometimes just doesn't come on.

The output of Roku 4 goes into a Vanco 280573 HDMI Audio Extractor. Analog audio from that goes to a Denon receiver; we're tolerating ProLogic for surround. The HDMI video output of the Vanco unit goes to a newish Samsung TV's HDMI input.

I have instructions for the Vanco unit, which basically says push the switch and leave it alone for a few seconds; if you get sound, it's set properly.

I need instructions for the Roku's audio settings. What happens is that audio sometimes works and sometimes doesn't. Perhaps different programming on the Roku has different audio characteristics; the audio settings instructions would tell me what the possibilities are.

Thanks in advance.