Modem connection speeds.. Reg hack?

I’m having problems connecting above 32kbps.. Ive tried 5 different systems, 5 modems, 3 locations (all with good phone lines), 3 access numbers, and 3 operating systems (Me, 98se, 95). Im using a 6 ft. phone cord so thats not it. I cannot connect any faster.. All the modem properties settings are correct… I have earthlink internet access. I know there are reg. hacks to speed up modems.. Anyone know of one that works or any suggestions on how to get higher connection speed?