I have hbo and showtime. Showtime on demand has sound but hbo on demand movies has no sound?
What error is icm1601?
If you are using a cable box, I'd check your Audio SAP settings and make sure Audio SAP is off. If it gets turned on by accidently, the result is no sound on one or a few channels, or channels that are in Spanish that shouldn't be. Here are some directions that I found online in case you have no idea what I'm talking about. https://www.spectrum.net/support/tv/sap-guide-instructions/
Are you watching on demand from a set top box or a mobile device?