Even though I didn't mess with the chd with the chdman.
D:\MAME>mame64 pbball96 pbball96.chd WRONG CHECKSUMS: EXPECTED: SHA1(ebd0ea18ff9ce300ea1e30d66a739a96acfb0621) BAD_DUMP FOUND: SHA1(6d47624e86f97c0b8ea4ebb84cc5446aa4f11fcf) WARNING: the game might not run correctly.