Every TIME we use the phone the broadband drops out.
The set up is like this
Main Socket> Sky (Double) > Phone + extension cable> filter> dsl > router > ethernet to pc

But when I try to place a filter into the main socket the connection completely goes with or without the phone. How should I have it set up?

Thanks

So I did some testing.
Test 1
The first test was plugging just the filter into the mains socket and then connecting a laptop to the router. The connection was fine. I then plugged the phone/sky into the filter as well and the connection was fine no drops. I did this test with three filters I had and all worked fine.

Test 2
I then connected the filter at the end of my extension that extends the phone socket upstairs. With the other end of the extension plugged into the main socket with phone/sky plugged in. All filters worked fine. But the phone caused the broadband to disconnect and the phone made FUNNY noises.

Test 3
I then rotated all filters, placing one directly into the main socket with phone/sky and an extension extending phone line upstairs with another filter at the end to plug dsl cable in. No internet connection what so ever. Phone fine.

Conclusion
filters seem fine as does the wiring as does router so what is the problem? Test 3 was the way I originally had it set up and it use to WORK fine.

I got TWO more brand new filters and tried them and still the same problems.