Any experience of noisy transformer on Jadis amps


One of my trannies on JA30 monos makes noise, you have to stand close to hear. It sounds like vibrating in conjunction with mains frequency. It annoys me and wonder if it could be its wire/coil loosened from anchor. Had a similar experience with a very old transformer were primary winding had loosened from paper surrounding anchor. On the other hand Jadis trannies propably have a different design.
Mine are from 1993.

Many thanks for advice and thoughts!
clabe
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Elizabeth gives good advice. You should also check to make sure that a mounting bolt is not loose, or that there is not excessive DC on your power line.
Hi Guys!
I tried tightening bolts without success.
Have to take the lid of to see how it looks inside transformer, maybe I can see or hear clearer where (if windings are loose).

Many Thanks!