hi all, The problem is the following: Using tcpdump -i sis0, whatever other arguments, I am loosing more or less (UDP) packets depending on the bitrate when starting AND stopping tcpdump. At least at the application level as reported by my client program. No such problem with the rl driver, not tested on others yet but that is possible if needed. I am using FreeBSD 6.1-STABLE #0: Thu Sep 7 13:06:10 CEST 2006 but it was the same with a 6.1RC. from dmesg: sis0: <NatSemi DP8381[56] 10/100BaseTX> port 0xbc00-0xbcff mem 0xdfffe000-0xdfffefff irq 7 at device 15.0 on pci0 sis0: Silicon Revision: DP83815D Please let me know if I can help with some other test/info. Regards, Roman.