2003 range rover vogue l322 radio, cd and tv

Can anybody help when the radio or the cd is playing the sound goes off for a split second every 5 seconds but there is no loss of power to the unit but where the programme number is displayed it goes off at the same time then back on when the sound resumes.The television is the opposite no sound for 5 seconds the sound for a split second.

Winny,

I've not had this exact same thing happen to my L322, but would suggest checking the amp connections in the boot equipment rack (behind the left cover in the boot area). This area can get damp and could cause (intermittent) connection corrosion/faults on various bits of kit with subsequent system wide issues. Is the sat nav 'voice' unaffected?

Steve