M-AUDIO MM401 - Manual (Page 5)

IMPORTANT: When using a DOS program, you need to make
sure that the interrupt/IRQ and address selected on your MM-
401 are also selected within your program. For example, if your
MM-401 is set to interrupt/IRQ 2 and address 330, you have to
make sure your sequencer is also set to interrupt/IRQ 2 and
address 330. To find out how to do this, you will need to look at
your program’s manual or call your program’s manufacturer.
Some older software may not allow you to change the interrupt
and will only work on interrupt 2. If this is the case you may
need to change the interrupt of conflicting devices instead of the
interrupt of the MM-401.
The dip-switches used to set the address and interrupt on the
MM-401 are located on the lower left hand side of the card as you
view it with the metal bracket on the right side. The switches are
numbered from right to left. Depending on when your card was
manufactured the switches may have “OPEN/CLOSED” label-
ing instead of “OFF/ON.” If this is the case “OPEN” is equal to
“OFF” and “CLOSED” is equal to “ON.”