Topic of problem Sometimes the internet suddenly does not work. With isdn-tools like isdnctrl, ifconfig or imon it shows that i am connected with the provider. But i can't open any Internetpage or ping any PC in the Internet. Logfiles With the maximum logging it says: Oct 31 10:17:04 superbyte kernel: NETDEV WATCHDOG: ippp0: transmit timed out Oct 31 10:17:04 superbyte kernel: isdn_tx_timeout dev ippp0 dialstate 0 Oct 31 10:17:04 superbyte kernel: ippp0: all channels busy - requeuing! Oct 31 10:17:44 superbyte kernel: NETDEV WATCHDOG: ippp0: transmit timed out The message repeats every 40 seconds, until i reconnect to the internet with isdnctrl hangup and dial. Hardware I use PCI Fritz Card v1.0 00:08.0 Network controller: AVM Audiovisuelles MKTG & Computer System GmbH A1 ISDN [Fritz] (rev 02) Interrupts: 5: 6762773 XT-PIC HiSax Kernel Linux version 2.4.22-mh1 (root@superbyte) (gcc version 2.95.4) Solution: The Isdn Driver is losing interrupts. Try to change the IDE Cable or other IDE Devices. In my case it was that the Kernel did not support IDE AMD/Nvidia. Compiling it in helped and in addition DMA worked afterwards (but even without DMA the Problem did not appear again)