BT Aviator 10M Signal Problems

Hi,

I have had a BT Aviator 10M for a while and use it with the indoor aerial that came with the unit. We regularly and now constantly seem to have recpetion issues with it, lots of chirps and digital distortion like a needle being dragged across a record.

Is it most likely down to poor signal strength (our little portable walkman type DAB has signal issues) or is there anything you could suggest that i can do to improve it. Running an external or loft aerial is not an option.

Is anyone aware of any software updates for this unit?

Many Thanks