This sounds very much like an OSCAM config issue. If the link that Sicilian provided doesn't help, you may want to join and ask for help over at the official OSCAM forums:
Code:
http://www.streamboard.tv/wbb2/portal.php
They'll want to see your exact configs and a full debug log.
I would also recommend trying the latest v8789 (at time of posting) version of OSCAM. Precompiled binaries can be downloaded from this site:
Code:
http://download.oscam.cc/index.php?&direction=0&order=mod&directory=1.20_TRUNK/mips-tuxbox-oe2.0