Somebody help!!

<p>We have been DSTV subscribers for a long time and i have never come accross this problem, there are various chanels that when we try to view them it gives a code saying... "Signal not found...check that your set-top box is properly connected to the cable point. If the problem persists, please call the Multichoice call centre for assistance."</p> <p>All the other channels work fine except for a select few</p> <p> </p> <p>I have called twice trying to rectify this problem and nobody can help me, i have done resets and return to factory settings and various other things yet this problem still persists</p> <p> </p> <p>Please can somebody sort this out..we pay a lot of money to view these channels</p>