Light dimming up and down on tick over

[Ash74]

As above when the car is ticking over (clio200) all the lights are dimming/flickering up and down a little this includes interior light as well. I have no ice installed either. Anyone got ideas how I can fix it?

 

[H182]

My clock light started dimming when the alternator was on the way out.

 

[bashracing]

as above alternator

 

[Ash74]

Cool thanks for your replies