MAME volume keys do nothing?

[Dekieon]

I was thinking of getting some buttons for volume for my MAME cab. However when I click the - and = in MAME to change the volume nothing happens. Should I be clicking something else to make these work? Does a setting need to be turned on somewhere to make these keys work? I can press the ` key and set the master volume, but I would prefer to use the volume keys that MAME says it has.

What am I doing wrong?

[boomstick]

Often wondered about this myself

[Ginsu Victim]

Give Cabvol a shot.
http://forum.arcadecontrols.com/index.php/topic,69901.0.html

[Endprodukt]

Mame volume keys are for games that had digital volume buttons  like blitz for example. Volume keys were often used in service mode too. Especially in racing games. You can find these on pinball games as well.

[gtxjoe]

There is another mame volume key, which is defaulted to the ` key (usually above the tab key).  Press that, a volume bar will show up and then try joystick left/right to adjust (or maybe joystick up and down

[Dekieon]

I see, I was hoping those buttons somehow controlled the volume for all games as I was going to add up/down volume buttons. I don't like the way the master volume control works using the joystick, so  I will have to get the volume control via the amplifier I suppose.

[Endprodukt]

I just soldered the volume put to the side of my control panel. Quick access and I rarely have to use it.