Tvheadend

hey everybody,

I've got a raspberry pi 2 running tvheadend as a server and two devices with kodi as clients. I use a PCTV TripleStick as a DVB-C receiver.
Everything runs great, even HD-TV except a few channels, which show a lot of artifacts. I recognized that these channels are all at mux 122 or lower.

A sample log:

2015-08-14 14:48:04.978 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 1)

2015-08-14 14:48:05.001 TS: DVB-C/122MHz/RTL: MPEG2AUDIO @ #1402 Continuity counter error (total 1)

2015-08-14 14:49:54.338 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 2)

2015-08-14 14:49:54.338 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 1)

2015-08-14 14:50:19.467 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 3)

2015-08-14 14:50:19.467 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 1)

2015-08-14 14:50:19.467 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 2)

2015-08-14 14:50:19.490 TS: DVB-C/122MHz/RTL: MPEG2AUDIO @ #1402 Continuity counter error (total 2)

2015-08-14 14:51:23.866 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 5)

2015-08-14 14:51:23.866 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 3)

2015-08-14 14:51:23.866 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 3)

2015-08-14 14:51:47.871 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 6)

2015-08-14 14:51:47.871 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 4)

2015-08-14 14:51:47.894 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 4)

2015-08-14 14:52:02.576 TS: DVB-C/122MHz/RTL Transport error indicator (total 1)

2015-08-14 14:53:17.301 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 7)

2015-08-14 14:53:17.304 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 5)

2015-08-14 14:53:17.304 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 5)

2015-08-14 14:53:41.061 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 8)

2015-08-14 14:53:41.062 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 6)

2015-08-14 14:53:41.062 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 6)

2015-08-14 14:53:51.310 TS: DVB-C/122MHz/RTL Transport error indicator (total 2)

2015-08-14 14:54:25.387 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 9)

2015-08-14 14:54:25.390 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 7)

2015-08-14 14:54:25.392 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 7)

2015-08-14 14:54:25.394 TS: DVB-C/122MHz/RTL: MPEG2AUDIO @ #1402 Continuity counter error (total 4)

2015-08-14 14:54:55.775 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 11)

2015-08-14 14:54:55.775 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 8)

2015-08-14 14:54:55.775 TS: DVB-C/122MHz/RTL: MPEG2AUDIO @ #1402 Continuity counter error (total 5)

2015-08-14 14:55:19.762 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 12)

2015-08-14 14:55:19.762 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 9)

2015-08-14 14:55:19.762 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 9)

2015-08-14 14:55:25.691 TS: DVB-C/122MHz/RTL: MPEG2AUDIO @ #1402 Continuity counter error (total 6)

2015-08-14 14:55:35.781 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 14)

2015-08-14 14:55:35.781 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 11)

2015-08-14 14:55:35.781 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 11)

2015-08-14 14:56:21.291 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 15)

2015-08-14 14:56:21.292 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 12)

2015-08-14 14:56:21.293 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 12)

2015-08-14 14:56:21.322 TS: DVB-C/122MHz/RTL: MPEG2AUDIO @ #1402 Continuity counter error (total 7)

2015-08-14 14:57:24.331 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 16)

2015-08-14 14:57:24.332 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 13)

2015-08-14 14:57:24.333 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 13)

2015-08-14 14:57:25.843 parser: transport stream AC3, DTS discontinuity. DTS = 53213500, last = 53081021

2015-08-14 14:57:28.700 TS: DVB-C/122MHz/RTL Transport error indicator (total 3)

2015-08-14 14:58:53.278 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 17)

2015-08-14 14:58:53.281 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 14)

2015-08-14 14:59:11.577 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 18)

2015-08-14 14:59:11.577 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 14)

2015-08-14 14:59:36.548 TS: DVB-C/122MHz/RTL Transport error indicator (total 4)

2015-08-14 15:00:05.752 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 19)

2015-08-14 15:00:05.752 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 15)

2015-08-14 15:00:05.752 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 15)

2015-08-14 15:00:07.409 parser: transport stream AC3, DTS discontinuity. DTS = 67757495, last = 67610615

2015-08-14 15:00:17.866 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 20)

2015-08-14 15:00:17.866 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 16)

2015-08-14 15:00:18.635 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 16)

2015-08-14 15:00:18.635 TS: DVB-C/122MHz/RTL: MPEG2AUDIO @ #1402 Continuity counter error (total 8)

2015-08-14 15:02:37.597 TS: DVB-C/122MHz/RTL Transport error indicator (total 6)

2015-08-14 15:03:43.141 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 22)

2015-08-14 15:03:43.141 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 18)

2015-08-14 15:03:43.144 TS: DVB-C/122MHz/RTL: MPEG2AUDIO @ #1402 Continuity counter error (total 9)

2015-08-14 15:04:20.771 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 23)

2015-08-14 15:04:20.771 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 19)

2015-08-14 15:04:20.771 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 17)

2015-08-14 15:04:42.502 TS: DVB-C/122MHz/RTL Transport error indicator (total 7)

2015-08-14 15:05:07.719 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 25)

2015-08-14 15:05:07.719 TS: DVB-C/122MHz/RTL: TELETEXT @ #1404 Continuity counter error (total 20)

2015-08-14 15:05:43.951 TS: DVB-C/122MHz/RTL: MPEG2VIDEO @ #1401 Continuity counter error (total 26)

2015-08-14 15:05:43.951 TS: DVB-C/122MHz/RTL: AC3 @ #1403 Continuity counter error (total 18)

Do you guys have any idea what causes these errors?
Thanks