I've read that the Satellite tuner, and canble, tuner, have different connections, so can't easily be switched, plus you would need to J Tag it, to alter the firmware.
Even when this was a reasonable receiver it didn't seem worth the effort, now it's so old it definitely isn't.
I have never owned any Dreambox, satellite, or cable, so can't confirm this information.
A couple of the VU+ models do have the option of fitting a terrestrial/cable tuner, but again is it worth it when, as Topper states, you can probably get a cheap cable set top box, for less than a VU+.