Help with wall socket

[tezb]

So just moved into a new flat, built 20 years ago, there a double pattres on the wall with SAT 1 and 2 f type socket, FM socket and return socket.

So when i plug TV in all is good and working but if i plug my DAB and FM radio into the socket i get no DAB radio and only 3 FM radio stations, we live 3 miles from transmitter antennas, Rye Hill, have both FM and DAB antenna on the roof but no signal to the flat.

I have checked the cables going to the sockets and all look good.

I contacted building maintance who sent a engineer to have a look and said he could find nothing wrong and had to be something wrong in the flat.

SO looking for advise as to what to do as it will cost me if i need to call them out

Many thanks