I stand to be corrected, but I believe that is an urban myth ?

Unless you stayed on the line for about 10 minutes

It is an urban myth. The most you should pay for a call at the moment is £1.53 per minute unless you ring from a mobile as the mobile phone companies put a huge surcharge on calls to Premium Rate numbers.

This will change next week when new charging comes in, the service provider will have to say what they receive from the call plus their phone companies charge and your phone company will have to tell you what they will charge you to send the call. As a result, calls from mobiles to high rate numbers will be cheaper but calls to low rate numbers will be much higher.

So it will be cheaper to phone a mucky service but dearer to phone an advice line

This is the OFCOM web site that explains it:

http://www.ukcalling.info/