I also increased values in
 
#define TS_SCRAMBLING_CONTROL  0xC0
#define TS_SCRAMBLING_TIMEOUT     5 // seconds to wait until a TS becomes unscrambled
#define TS_SCRAMBLING_TIME_OK    15 // seconds before a Channel/CAM combination is marked as known to decrypt
still the same.
 
May  4 10:33:34 localhost vdr: [1348] info: Channel not available!
May  4 10:33:45 localhost vdr: [1348] switching to channel 21
May  4 10:33:45 localhost vdr: [1535] transfer thread started (pid=1348, tid=1535)
May  4 10:33:45 localhost vdr: [1536] receiver on device 1 thread started (pid=1348, tid=1536)
May  4 10:33:46 localhost vdr: [1537] TS buffer on device 1 thread started (pid=1348, tid=1537)
May  4 10:33:48 localhost vdr: [1352] ERROR: CAM 2: session for resource identifier 00400041 already exists (1/1)
May  4 10:33:51 localhost vdr: [1535] transfer thread ended (pid=1348, tid=1535)
May  4 10:33:51 localhost vdr: [1537] TS buffer on device 1 thread ended (pid=1348, tid=1537)
May  4 10:33:51 localhost vdr: [1536] buffer stats: 126148 (6%) used
May  4 10:33:51 localhost vdr: [1536] receiver on device 1 thread ended (pid=1348, tid=1536)
May  4 10:33:56 localhost vdr: [1348] switching to channel 21
May  4 10:33:56 localhost vdr: [1348] buffer stats: 45120 (2%) used
May  4 10:33:56 localhost vdr: [1348] info: Channel not available!
May  4 10:34:07 localhost vdr: [1348] switching to channel 21
May  4 10:34:07 localhost vdr: [1556] transfer thread started (pid=1348, tid=1556)
May  4 10:34:07 localhost vdr: [1557] receiver on device 1 thread started (pid=1348, tid=1557)
May  4 10:34:07 localhost vdr: [1558] TS buffer on device 1 thread started (pid=1348, tid=1558)
May  4 10:34:09 localhost vdr: [1352] ERROR: CAM 2: session for resource identifier 00400041 already exists (1/1)
May  4 10:34:13 localhost vdr: [1556] transfer thread ended (pid=1348, tid=1556)
May  4 10:34:13 localhost vdr: [1558] TS buffer on device 1 thread ended (pid=1348, tid=1558)
May  4 10:34:13 localhost vdr: [1557] buffer stats: 121260 (5%) used
May  4 10:34:13 localhost vdr: [1557] receiver on device 1 thread ended (pid=1348, tid=1557)
May  4 10:34:18 localhost vdr: [1348] switching to channel 21
May  4 10:34:18 localhost vdr: [1348] buffer stats: 44744 (2%) used
May  4 10:34:18 localhost vdr: [1348] info: Channel not available!
May  4 10:34:18 localhost kernel: dvb_frontend_ioctl: DVBFE_GET_INFO
May  4 10:34:18 localhost kernel: dvb_frontend_ioctl: FESTATE_RETUNE: fepriv->state=2
 
Pierre