In reply to La Shamster:
> (In reply to Hairy Pete)
>
> Sorry guess the use of everything was confusing. I only have one base unit phone together with the additional phone that receives the wireless signal from the base unit in a different room.
>
Beg, borrow or steal a wired phone that you know works. Plug it, and only it, into the master socket. If it works try your base unit next, etc..
> Everything was working fine until a week ago when I first realised I wasn't receiving calls.
I'm with STG on this! However, there are other side effects that you might worry about. If the line is being held when you make out-going calls you could be racking up a huge bill, i.e. your two minute call plus however long it takes to clear the line.
>
> Why can I make calls without problems but not receive?
Gezzz ask the technical questions won't you? You might have noticed, or not, that there are only two telephone wires that enter your house (I assume you're on the standard BT system - none of this fancy "cable" or such like). Aside from the speech signal (and internet) these two wires have to communicate the state of the phone, i.e. off-hook, or on hook, based on technology that was available about 100 years ago. When the receiver is down, only the bell circuit is connected, by an AC coupling, to the exchange. So the exchange can ring the bell. When you pick-up the receiver the exchange needs to know this so that it can turn-off the ringing circuit and connect the speech circuit. Your telephone indicates the off-hook state by allowing a DC current to flow. The off-hook state is how you normally dial-out, which explains why you can still make out-going calls.
It sounds as if something that you have connected, possibly your base unit, is leaking DC and therefore tricking the exchange into thinking that you've lifted the receiver. The voltages used to ring the bell are much higher than the normal, off-hook voltages, hence the first ring might be triggering the fault in whatever device you have connected.