O.K. I finally got my sound back. Know what the problem was? A loose jumper on the audio board. The computer wizard . . . Tom Leufkens . . . found it. Thanks, Tom.
So, I finally have my new computer monitor fully operational. It's a huge picture, which is very good for these old eyes. The screen is 21.6 inches wide. I make that out to be a 22 inch screen, don't you? And it's a flat screen so I finally have some writing room on my desk.
Your Catalyst is a happy camper.