Cryptopay to lose the phone line, unless you want to spend something like $5000 for a D.A.N. system and ethernet adapter only to pay more processing fees.
Is your dial-up processing slow? I've found that it usually only takes 10 seconds after the "Please wait while your
transaction is processed" plays to be done. You may lose the cost of a phone line but you'll pay more inprocessing for a few seconds.