Yamaha A3000 Owner's Manual page 308

MIDI Function
Knob 3
Knob 4
Chapter 8 UTILITY Mode
306
Omni = off, on
Set this value on to enable reception over all channels.
Note that setting the value to on disables the Basic Channel setting that you make with
Knob 2, since the A3000 will accept note messages, program-change messages (if
PgmChange=on; see below), and control-change messages over all channels.
PgmChange = off, on
The setting determines whether the A3000 accepts program-change messages.
on
The A3000 accepts program change messages. Specifically, the
A3000 will change programs in response to program-change
messages received over the Basic Receive Channel (if Omni=off),
or over any channel (if Omni=on).
off
The A3000 will never switch programs in response to program-
change messages.