Yes. Generally speaking, 'foo' bios roms go into the 'foo.zip' file in the designated 'roms' folder.
PS: 'mame foo -listcrc' helps
Actually if I recall correctly, 'Puckman' by Namco is the original (and came first), and then they licensed the property to Midway which then released 'Pacman' (which therefore is correctly listed as a 'clone' of Puckman in MAME).
My 'mame.ini' has a 'volume' setting, which is set to '0'. I haven't tested it, but I assume you can set it to the desired value there ?