Quoted from... [Link: remotecentral.com]

Here it is...

The M3000 has no discretes and never will.
The M4000s in the wild right now have no discretes. There
will be a running change in late June/Early July where
discretes will be added and when we get our first shipment
that have the discretes I will post again in this thread
and probably start a new one.

The exception is the 19" M4000 on our showroom floor right
now that was built in March of '08 which does respond
to discretes. My guess is that the smaller sets were built
in a different factory that had the discrete codes in
their software and the larger sets were built in a different
factory that didn't have the discretes in their software.

For the record, the discrete ON and OFF DO WORK
but these are the only discretes that do work.

The only workaround I can find is to go into the menu
and turn off "Input Auto Arrange" and go back to the old
CH+, pause, TV/VIDEO, pause, TV/VIDEO and count to the
input you need. I would also go in and turn off the inputs
you're not using to keep the command count down.