I just worked with Oppo support today, after sending them an email this morning. They wanted to trouble shoot, rather than have me send the unit in. Turns out, a firmware upgrade and a factory reset solved the problem-- no audio from either the hdmi or the analog outputs. I still have to check the analog outputs, which for reasons not worth explaining, I could not do in my living room set up at present.
Pretty impressive given that I bought the unit second hand several years ago.