BT Graphite "Range Out " disply fault?

We have a BT Graphite 1500 with 2 cordless phones and a base station with answering machine

Both phones have suddenly failed and now display "Range Out"

I have been on the BT help page and run through their suggestios
1..Switch Mains off 5 second then reconnect
2...Remove and replace phone batteries
3..Do a "factory reset on both phones

Still fail to work (no outgoing and incoming does not ring the phones..only switches to answering machine after 10 seconds)

I suspect that there will be something amiss with the base station

I have tried ringing the free BT Helpline 0808 100 6556....but gave up after 30 minutes with no answer from a human being ..only "your call is important to us....blah..blah..blah..)

Anyone have any further suggestions please

Disgruntled
October 2010