winxp/2k DUN errors

ok i've got 2 systems both dual booting win98se, winxp pro and win2k pro. i have the following 2 modems, a usr performance pro v.92 internal modem and a creative labs external v.92 modem.
comp a is the host machine with the ext. modem installed. comp b is the client machine with no modem installed. in win98 i have no problems with connection speed or maintaining connections. in win2k or xp if i'm playing an online game there's no problem. as soon as i start to browse the netthe net status monitor starts showing errors on the recieving side. after an error the connection stops recieving for about 10 seconds then resumes at about half the throughput.
i'm not using the internal modem because of EMI from the motherboards and periphials were causing line noise. though the same problem occurred with the internal modem.
another thing i've noticed is after a couple errors when i try to disconnect it can take from 30-60 seconds to disconnect.

if anyonw has any ideas please let me know. it's really getting annoying haveing to reconnect every couple web pages