Tvheadend

hi all!
i have a streamer on Ubuntu 10.04.4LTS and TBS6984 dvbs2 card and tvheadend (tvheadend-3.4patch1). Client is VLC 2.1.3 with GPU h264 enabled decode.

SD channels works fine, but HD channels no..

i try to stream HD channel from dvbs2 mux to client through tvheadend and get many Audio/Video buffers lost on client and many artefacts on screen.

in tvheadend logs i see many Continuity counter errors:
Feb 26 00:11:31.894 [WARNING]:TS: TurboSight TBS 6984 DVBS/S2 frontend/: 12,130,260 kHz Right (Default (Port 0, LNB))/HD: H264 #305: Continuity counter error
Feb 26 00:11:47.269 [WARNING]:TS: TurboSight TBS 6984 DVBS/S2 frontend/: 12,130,260 kHz Right (Default (Port 0, LNB))/HD: H264 #305: Continuity counter error
Feb 26 00:12:23.649 [WARNING]:TS: TurboSight TBS 6984 DVBS/S2 frontend/: 12,130,260 kHz Right (Default (Port 0, LNB))/HD: MPEG2AUDIO @ #405: Continuity counter error

first i thought that TBS dvbcard driver for linux is broken, but no.

I checked these configurations with same dvbs2 hd channel with astra (https://cesbo.com/en/solutions/streaming/ - it's opensource dvb/iptv streaming app):

1. astra (decode dvb channel) -> astra udp stream -> vlc client = there is no Audio/Video buffers lost!
2. astra (decode dvb channel) -> astra http stream -> vlc client = there is no Audio/Video buffers lost!
3. astra (decode dvb channel) -> astra udp stream -> tvheadend http stream -> vlc client = a lot of Audio/Video buffers lost with many errors like these:
Feb 25 23:17:26.482 [WARNING]:TS: eth0/239.0.199.3: H264 #303: Continuity counter error
Feb 25 23:17:26.482 [WARNING]:TS: eth0/239.0.199.3: MPEG2AUDIO #403: Continuity counter error

also i checked other HD channels with bitrate from 5mbit to 17 mbits and in all time i see Audio/Video buffers losts on VLC client if i used confin_3 = (astra (decode dvb channel) -> astra udp stream -> tvheadend http stream -> vlc client), but with config 1 and config all is fine!

Maybe not enough buffers for tvheadend and i should tuning some buffers or something like this?

i tune buffers like this:
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.core.rmem_default = 16777216
net.core.wmem_default = 16777216

but it does not help.
can some one help me?