Sony sterio cutting out?

[Damo]

Hi guys inly recently my sony sterio has started cutting out when volumes turned up mainly at night when light an stuff are on any one any ideas why? Nothings been changed wiring wise an sterios been in a few months now but it was a plug an play jobbie from my old sterio......

Damo.

[Stuart]

Your battery and or alternator aren't up to the job of supplying current for the lights AND stereo .

[Damo]

Your battery and or alternator aren't up to the job of supplying current for the lights AND stereo .
Just what I thought tbh stu.... Just wanted to confirm :).

damo.