I need some help understanding why this is happenning. I have a Panasonic A310 DVD, an APEX 5131 DVD, and a Yamaha DSP receiver/amp. The Yamaha and the APEX have a special display when digital is present. The panasonic's is on screen on demand. When I use a dolby digital DVD, either by default on a dvd, or by dvd menu selection, on the Panasonic, the on screen display will show digital, but the receiver will show pro-logic (5.1). If I switch the dvd menu item to 5.1 instead of digital, it shows 5.1 on the panasonic display but digital on the Yamaha!

When doing this on the APEX, both say digital at the same right time.

Why would things be flip-flopped on the panasonic? Which should I trust, the panasonic dvd player or the yamaha display driven by auto-detecting digital?? Is there a simple test?

Thanks.