TD4 battery running flat, radio doesn't work, any suggestions?

Hi, the radio of my TD4 keeps running flat and i cannot pin point the problem. The radio lights up, but nothing on it seems to work. Doesnt anyone know if these two are related and how to diagnose/solve this issue? thanks in advance

Welcome to the landyzone wet floor and mop users. Be worth pursuing the question in the Freelander section for a better answer.
Pending on the age of the battery normally after 3-4 if can throw a wobbler. Check the voltage before charge then after charge. Some batteries have indicated colour green red. You may get small power but not enough to start the engine.