The Problem
If you are “lucky”, you will know you have a loose jack socket nut because you can feel with your fingers or when plugging in your lead that the socket is loose.
If you are not so lucky, you can spend some time trying to track down that strange rattling sound that is spoiling your playing and your enjoyment of the guitar to a loose jack socket nut. This is what I went through with this lovely Hanika 58 fitted with an AER pickup.
The owner complained of a noise which at first appeared to be fret buzz from low action. Fitting an oversize saddle to give an exaggeratedly high string action failed to stop the noise so this cause was ruled out. Next I tried replacing the g3 string which was showing the problem most; the noise persisted with a new string. I had a feel for loose machine heads – a rattle there can sound like it is coming from the soundboard, but all seemed OK. Then had a look inside with a mirror to see if any wires were loose or touching the soundboard – I secured them all away from the soundboard and back with tape but still the problem persisted.
Then listening to the noise more carefully it was clearly metallic – I should have heard this sooner but you can’t always be super efficient. There isn’t much that is metal on a classical guitar and so the jack socket was the obvious place to look and, sure enough, a slight movement could clearly be felt when shaking it with the fingers.
The Solution
This was much less time consuming than the diagnosis.
- Protect the working area with masking tape
- Loosen and remove the cover – this should be possible with your fingers; if the cover is tight and you are in danger of turning the barrel then you will need to get your arm inside the soundhole so that you can hold the rear of the barrel (a pre amp is fitted to it) to prevent it from turning. When the cover is removed you will see that the barrel of the jack socket on this AER has a small hole through it
- Hold the barrel in position and prevent it from turning with a very small allen key held in one hand and, using a flat 13mm spanner (for the AER), carefully tighten the retaining nut – it should be tight but no over-tight
- Screw the cover back into place
 |  |
 |  |
Not all jack sockets are the same as this AER and if yours does not have the small securing hole through it then you will have to hold the barrel in place from the inside of the guitar while you are tightening the nut from the outside. This is significantly more difficult and you may want to ask someone who has done it before for some assistance or advice!