Вот лог

Date/Time Facility Severity Message
Jan 1 00:00:26 daemon info pppd[272]: Plugin pppoe loaded.
Jan 1 00:00:27 daemon info pppd[272]: RP-PPPoE plugin version 3.3 compiled against pppd 2.4.3
Jan 1 00:00:27 daemon info pppd[272]: Plugin pppoe called.
Jan 1 00:00:28 daemon notice pppd[272]: pppd 2.4.3 started by admin, uid 0
Jan 1 00:00:30 daemon info pppd[272]: PPP session is 58202
Jan 1 00:00:30 daemon info pppd[272]: Using interface ppp0_0_33_1
Jan 1 00:00:30 daemon notice pppd[272]: Connect: ppp_0_0_33_1 <--> nas_0_0_33
Jan 1 00:00:30 daemon warn pppd[272]: Couldn't increase MRU to 1500
Jan 1 00:00:30 daemon notice pppd[272]: PAP authentication succeeded
Jan 1 00:00:30 daemon notice pppd[272]: peer from calling number 00:1F:9E:19:BE:AA authorized
Jan 1 00:00:31 daemon notice pppd[272]: local IP address 109.187.148.253
Jan 1 00:00:31 daemon notice pppd[272]: remote IP address 83.174.192.31
Jan 1 00:00:31 daemon notice pppd[272]: primary DNS address 83.174.192.227
Jan 1 00:00:31 daemon notice pppd[272]: secondary DNS address 83.174.192.228
Jan 1 00:00:32 user debug syslog: route add default gw 83.174.192.31 2>/dev/null
Jan 1 00:00:32 user debug syslog: iptables -A FORWARD -o ppp_0_0_33_1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Jan 1 00:00:32 user debug syslog: iptables -A FORWARD -i ppp_0_0_33_1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Jan 1 00:00:32 user debug syslog: echo > /proc/net/ip_conntrack
Jan 1 00:00:32 user debug syslog: echo "600" > /proc/sys/net/ipv4/ip_conntrack_max
Jan 1 00:00:32 user debug syslog: echo 2000 > /proc/sys/net/ipv4/netfilter/ip_conntrack_generic_timeout
Jan 1 00:00:32 user debug syslog: echo 600 > /proc/sys/net/ipv4/netfilter/ip_conntrack_tcp_timeout_established
Jan 1 00:00:32 user debug syslog: echo 1400 > /proc/sys/net/ipv4/netfilter/ip_conntrack_tcp_timeout_fin_wait
Jan 1 00:00:32 user debug syslog: echo 120 > /proc/sys/net/ipv4/netfilter/ip_conntrack_tcp_timeout_time_wait
Jan 1 00:00:32 user debug syslog: echo 4096 > /proc/sys/net/ipv4/ipfrag_high_thresh
Jan 1 00:00:33 user debug syslog: echo 1024 > /proc/sys/net/ipv4/ipfrag_low_thresh
Jan 1 00:00:33 user debug syslog: echo 5 > /proc/sys/net/ipv4/ipfrag_time
Jan 1 00:00:33 user debug syslog: iptables -t nat -D PREROUTING -i br0 -d 192.168.1.1 -p udp --dport 53 -j DNAT --to 128.9.0.107 2>/dev/null
Jan 1 00:00:33 user debug syslog: iptables -t nat -D POSTROUTING -o ppp_0_0_33_1 -s 192.168.1.0/255.255.255.0 -j MASQUERADE 2>/dev/null
Jan 1 00:00:33 user debug syslog: iptables -t nat -A POSTROUTING -o ppp_0_0_33_1 -s 192.168.1.0/255.255.255.0 -j MASQUERADE
Jan 1 00:00:33 user debug syslog: iptables -t nat -D PREROUTING -i br0 -d 192.168.1.1 -p udp --dport 53 -j DNAT --to 83.174.192.227 2>/dev/null
Jan 1 00:00:33 user debug syslog: iptables -t nat -A PREROUTING -i br0 -d 192.168.1.1 -p udp --dport 53 -j DNAT --to 83.174.192.227
Jan 1 00:00:33 user debug syslog: /bin/dnsprobe &
Jan 1 00:00:33 user notice dnsprobe[380]: dnsprobe started!
Jan 1 00:00:34 user debug syslog: echo 4096 > /proc/sys/net/ipv4/ipfrag_high_thresh
Jan 1 00:00:34 user debug syslog: echo 1024 > /proc/sys/net/ipv4/ipfrag_low_thresh
Jan 1 00:00:34 user debug syslog: echo 5 > /proc/sys/net/ipv4/ipfrag_time
May 26 09:41:20 user warn kernel: AdslCoreEcUpdTmr: timeMs=1800040 ecUpdMask=0x40000
May 26 10:02:12 user debug kernel: UDP: bad checksum. From 118.68.88.62:48607 to 109.187.148.253:1024 ulen 111


Остановилась закачка и у "аськи" вылет! в чем проблема?
вот параметры линии
Mode: G.DMT
Type: Interleave
Line Coding: Trellis On
Status: No Defect
Link Power State: L0

Downstream Upstream
SNR Margin (dB): 19.8 11.0
Attenuation (dB): 20.0 11.5
Output Power (dBm): 12.2 19.8
Attainable Rate (Kbps): 12224 1364
Rate (Kbps): 8160 1024
K (number of bytes in DMT frame): 256 33
R (number of check bytes in RS code word): 0 0
S (RS code word size in DMT frame): 0.5 1
D (interleaver depth): 2 1
Delay (msec): 0 0

Один пакет пришёл с некорректной контрольной суммой.
Остальное в логах всё нормально, параметры линии тоже хорошие. Это происходит систематически?

Повторно в логе эта строчка не появляется но закачка с аськой вылетают!Можно сказать что систематически!В режиме моста таких проблем нет!Модем что ль глючный?
May 26 13:48:11 user debug kernel: UDP: bad checksum. From 99.12.141.124:10864 to 109.187.172.111:30228 ulen 111
May 26 14:01:27 user warn kernel: AdslCoreEcUpdTmr: timeMs=1800195 ecUpdMask=0x40000