1 are all conections tight and clean
2 is the tit on the mogle base not burnt
3 is the bulb in the right direction U universal, V vertical H horizonal
4 have you replaced the bulb with a new one, you always need a spare
5 bulbs usualy take about 3-5 min. to fire up, and there is alway a flicker in the starting globe.
I would just get another bulb and test it. I have ballast and caps that are over 25 years old and no problems.
O yea always clean you bulb before use and leave NO finger prints.