well firstly you need to check if you can pause it using the buttons on the front of the box, if you can then you have a faulty remote. If not then you could have a problem with the HDD.
Try this
HDD reset and then a forced software download.
Start by turning the power off at the wall, then hold the left and right buttons (either side of select) on the front of the box and hold firmly for around a minute. The circle at the front of the box will illuminate, release the two buttons and press the select button. The light will now rotate anti clockwise, once this has finished turn the power off again and hold the backup button, turn the power back on and wait for all lights on the fron t of the box to illuminate. "Updating System Software" will be displayed on the screen.
WARNING this will erase everything on the HDD!
Hope this helps
Andy Brown, May 2010