Ballast problem
 

I changed all 3 bulbs yesterday as I thought 2/3 looked rather dim. Turns out it must be my ballast as 2/3 new bulbs look really dim too. I am not sure what to do, can these things be fixed? I must say I am very disappointed as this Hamilton set-up is only about 14 months old. The ballast has 2 switches on the box, 1 is for the 1 bulb, and the other runs 2 other bulbs and the fan. Any ideas for a solution?

Are the bulbs compatible with the type of ballast you are using?

Or am I reading this wrong? Is one of the ballast firing properly?

The bulbs are also Hamilton and are the right type and wattage. The ballast that runs a single bulb is working properly but the other one that runs the other 2 bulbs isn't. They are however both built into the same housing but with seperate switches.