Many thanks to those who suggested a replacement lithium battery is likely to solve the problem - it seems pretty unanimous and your help is very much appreciated.
Any suggestions as to who/where I could take the Beomaster 6500 to in order to get this replacement carried out?
Ideally, I would like to find someone in the Midlands/North West of England as I would rather take the unit to them as opposed to mailing it. The Beomaster is in 'as new' condition cosmetically and I need to find someone that will treat it with the same care and attention as I have.
Again, many thanks for your suggestions,
ferrari458spider