Technical radio volume keeps increasing

[scotty 1450]

Sorry new to this site so may be posting in the wrong place. Fiat Scudo 120 M jet. 2007. Radio volume keeps increasing wether moving or stationery. Bought a 2nd hand radio & it does the same. The intermittent beep means it needs to be coded to the van, but now I've got 2 problems instead of 1. Any help or a set of ear plugs would be very welcome.