Fluorescent lamps have current.

The ballast is not broken, it is caused by looseness. Relaxation includes several aspects:

1. There is a gap between iron cores, resulting in vibration and sound.

2. Loose between iron core and shell.

3. Loose between ballast and the whole shell.

If you don't want to buy a new one, you can try to deal with it like this: for 1 and 2, take it out if you can dip it in paint, and if you can't dip it in paint, use 502 instant-drying glue to drop it into the gap to make it not loose. For 3, just tighten the fastening screws.

Generally, after this treatment, there will be no more noise.