Moin,
ich habe die ganze Sache noch mal ein bisschen beobachtet. Der Rechner nutzt nach dem Senderwechsel einige Minuten die VDPAU-Unterstützung, dann laufen Puffer voll und die beiden CPU's müssen den Job übernehmen:
heiner@vdr2:~$ sudo tail -f /var/log/syslog
Jan 18 18:15:49 vdr2 vdr: [3421] buffer usage: 20% (tid=3420)
Jan 18 18:15:49 vdr2 vdr: [3421] TS buffer on device 1 thread ended (pid=3239, tid=3421)
Jan 18 18:15:49 vdr2 vdr: [3420] buffer stats: 2097151 (100%) used
Jan 18 18:15:49 vdr2 vdr: [3420] receiver on device 1 thread ended (pid=3239, tid=3420)
Jan 18 18:15:49 vdr2 vdr: [3425] receiver on device 1 thread started (pid=3239, tid=3425)
Jan 18 18:15:49 vdr2 vdr: [3426] TS buffer on device 1 thread started (pid=3239, tid=3426)
Jan 18 18:15:49 vdr2 vdr: [3425] cVideoRepacker: operating in H.264 mode
Jan 18 18:15:50 vdr2 vdr: [3425] SetBrokenLink: no GOP header found in video packet
Jan 18 18:15:54 vdr2 vdr: [3424] Text2Skin: channelInfo display update thread ended (pid=3239, tid=3424)
Jan 18 18:17:01 vdr2 CRON[3448]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Jan 18 18:18:50 vdr2 vdr: [3426] buffer usage: 70% (tid=3425)
Jan 18 18:18:50 vdr2 vdr: [3426] buffer usage: 60% (tid=3425)
Jan 18 18:18:50 vdr2 vdr: [3426] buffer usage: 70% (tid=3425)
Jan 18 18:18:50 vdr2 vdr: [3426] buffer usage: 80% (tid=3425)
Jan 18 18:18:51 vdr2 vdr: [3426] buffer usage: 90% (tid=3425)
Jan 18 18:18:51 vdr2 vdr: [3426] buffer usage: 100% (tid=3425)
Jan 18 18:18:55 vdr2 vdr: [3426] ERROR: driver buffer overflow on device 1
Jan 18 18:18:56 vdr2 vdr: [3425] ERROR: skipped 11 bytes to sync on TS packet on device 1
Jan 18 18:18:56 vdr2 vdr: [3425] TS continuity error (12)
Jan 18 18:18:56 vdr2 vdr: [3425] TS continuity error (9)
Jan 18 18:18:57 vdr2 vdr: [3425] PES packet shortened to 5054 bytes (expected: 6158 bytes)
Jan 18 18:18:57 vdr2 vdr: [3425] cAudioRepacker(0xC0): skipped 432 bytes to sync on next audio frame
Jan 18 18:18:59 vdr2 vdr: [3426] ERROR: driver buffer overflow on device 1
Jan 18 18:19:00 vdr2 vdr: [3425] ERROR: skipped 11 bytes to sync on TS packet on device 1
Jan 18 18:19:00 vdr2 vdr: [3425] TS continuity error (8)
Jan 18 18:19:00 vdr2 vdr: [3425] TS continuity error (3)
Jan 18 18:19:01 vdr2 vdr: [3425] PES packet shortened to 4870 bytes (expected: 6158 bytes)
Jan 18 18:19:02 vdr2 vdr: [3426] ERROR: driver buffer overflow on device 1
Jan 18 18:19:04 vdr2 vdr: [3425] ERROR: skipped 11 bytes to sync on TS packet on device 1
Jan 18 18:19:04 vdr2 vdr: [3425] TS continuity error (0)
Jan 18 18:19:04 vdr2 vdr: [3425] TS continuity error (8)
Jan 18 18:19:04 vdr2 vdr: [3425] PES packet shortened to 4870 bytes (expected: 6158 bytes)
Jan 18 18:19:06 vdr2 vdr: [3426] ERROR: driver buffer overflow on device 1
Jan 18 18:19:07 vdr2 vdr: [3425] ERROR: skipped 11 bytes to sync on TS packet on device 1
Jan 18 18:19:07 vdr2 vdr: [3425] TS continuity error (10)
Jan 18 18:19:07 vdr2 vdr: [3425] PES packet shortened to 5054 bytes (expected: 6158 bytes)
^C
Gruß Heiner