Hi,
We have a Denon AVR 2700 receiver that is hooked up to our TV, DVD, VCR. 
We also have Direct TV.

Everything was working fine.  Last night I hit the wrong button on the
remote control, and now I am not getting any sound when the receiver
is in DVD mode or VCR mode.  Out of frustration, I pressed a bunch of
buttons on the receiver and on the remote so I'm sure I didn't help
the situation.
I asked a friend and  was told to make sure the tape monitor is in the
off position and that the receiver is in analog mode. It still doesn't
work.

None of the wiring was touched at all.

The sound still works when it is on TV mode.  I don't have a manual.
 
How can I get the sound to work when in DVD and VCR Mode? How can I
set up the receiver so it works with my DVD and VCR?

Thanks!