MPD and ADSL pptp line problems

[Arjan Knepper]

Hello,

We 're using FreeBSD-4.10 with mpd-3.18 to connect to our ISP through a 
Alcatel speed touch home ISDN-ethernet modem.
 From time to time the connection becomes verry slow and ping -f shows 
packet losses up to 90 %.
To recover form the losses, power cycling the modem OR stopping & 
restarting mpd OR waiting for minutes to hours solves the packet losses.

Any ideas what might cause this? And how to solve this?

The Alcatel Modem firmware is up-to-date.
There is absolute no problem between de modem and the FreeBSD-box.

Any help/suggestions would be appreciated.

Thanks.
Arjan