From your logs
Sep 30 10:06:09 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754108
Sep 30 10:06:19 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754109
Sep 30 10:06:29 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754110
Sep 30 10:06:40 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754111
Sep 30 10:06:50 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754444
Sep 30 10:07:00 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754445
Sep 30 10:07:10 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754446
Sep 30 10:07:21 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754447
Sep 30 10:07:31 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754472
Sep 30 10:07:41 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754473
Sep 30 10:07:51 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754475
Sep 30 10:08:01 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754480
Sep 30 10:08:12 HDPVR kernel: print_req_error: I/O error, dev mmcblk0, sector 2754482
[ 83.044620] print_req_error: I/O error, dev mmcblk0, sector 2754444
[ 93.284547] print_req_error: I/O error, dev mmcblk0, sector 2754445
[ 103.524606] print_req_error: I/O error, dev mmcblk0, sector 2754446
[ 113.764622] print_req_error: I/O error, dev mmcblk0, sector 2754447
[ 124.004609] print_req_error: I/O error, dev mmcblk0, sector 2754472
[ 134.244619] print_req_error: I/O error, dev mmcblk0, sector 2754473
[ 144.484559] print_req_error: I/O error, dev mmcblk0, sector 2754475
[ 154.724651] print_req_error: I/O error, dev mmcblk0, sector 2754480
[ 164.964600] print_req_error: I/O error, dev mmcblk0, sector 2754482
Looks like a defective SD card.