PROBLEM WITH MODEM CONNECTING TO ISP

Have PIII, WIN98, Lucent WinModem. Out of the blue have lost easy to get 44k connection to ISP. Now have to have another phone off of the hook in house, or cordless phone turned on to connect at 4K. Have ran phone line to another jack with no improvement. No changes that I can think of, phone line was running thru surge protector. Whats up???