I GOT IT WORKING!
I had the same VR-405 and the same thing was going on.
I talked with a tech guy for a while trying to trouble shoot it.
Basically if you have a receiver with auto mode on, then you should be playing a DVD that has a Dolby Digital logo on it --- your DVD player needs to have the correct settings for AUDIO (select the Digital Audio and choose ALL) or something close to it. I found that the DVD must me playing in Dolby Digital 5.1 mode or the receiver doesn't recognize it until it receives it!
Ok, ok.. I will get to the point.. so I had all of this correct, but still having problems... For some odd reason I got mad and didn't turn on my TV set (which is connected to the DVD with an HDMI cord) I turned on my DVD player and then receiver just to test some noise.... VIOLA IT WORKED. It switched to Dolby DIGITAL! FIRST TIME! YES>..... so then I quickly turned on my TV (HP 37 inch HDTV) and all of a sudden it clicks over to Pro Logic --- WTF.......
So now I was getting closer, and when the TV came on, it said non hdcp compliant on the screen... humm... either it is my TV or DVD.. I quickly checked my TV and it was HDCP compliant and was fine. But my DVD player had an old firmware on it making it NON compliant with Digital Audio Coaxial. So I downloaded the firmware to a CD and then put it in my DVD player and updated the firmware! AND VIOLA IT WORKED WHEN THE TV SET IS ON NOW!
Hope this helped someone.