On Sun, 11 Nov 2018, Steve Hodgson wrote:

I've just bought a Grundig Satellit 700 but I have problems with the FM
performance. I've been delighted with in the last few weeks, but now
there's no signal strength and audio is very poor.

This is the same with either the internal aerial or an external Dynalab
FM aerial.

Could this be an obscure setting or a fault?

I paid $2.00 for my 700 at a Rotary Club garage sale, I thought the price
read higher. That was after buying a 500 at some other group's sale a few
years before, I paid forty for that, and I probably could have gotten it
for less, but there was no price so I offered "high".

I found that both worked a lot better after I opened them up and unplugged
and replugged the various connectors inside. There are two boards, or
maybe three, and lots of interconnecting wires, and they all detach
through connectors. Unplugging and replugging made sure they were all
making good contact.

There might be other reasons, but this is an easy first step.

Michael