Fluorescent tubes when they start to flicker what do you change?

The Florescent is flickering know I need to change the bulb but how do I know if I need to change the starter as well? They are 4 tubes and 4 starters in each light fitting. How do I know if the starter as gone as well? Because it seems to work with 3 starters as well.Fluorescent tubes when they start to flicker what do you change?
Most fluorescent tubes these days use high efficiency ballasts that are self starting. Only very old ones use starters.



In case you have one, get one new starter, try one at a time in each fluoro which should end up telling you which ones need a new one. Then buy just what you need. If the starter doesn't fix any, then replace the tube.Fluorescent tubes when they start to flicker what do you change?
Not sure if it is a starter or something else but when mine flickered i changed the small round 'thing'(lol) hidden underneath the bulb in the middle. Mine worked fine after that! Good Luck x