Volume auto-lower itself to 0 randomly - iPod nano 6th gen

Greetings,

iPod nano 6th gen / 1.54'' Multitouch/Clip; Model MC696LL / A1366 (EMC2385).

The iPod recently started by itself to lower down its volume to 0 at random times. I mostly ever adjusted the volume of the iPod via the headphones buttons for years; the volume buttons, both + and -, on the iPod itself clicks twice when pressed (once when pressed and once when released) and the mechanical components of the volume buttons seems to be working quite well still and both similar (as in aging). I tried to 1) power off the iPod (by holding the power button); 2) hard reset it (holding volume - button with the power button); 3) empty it full charge; 4) unplug the 3.5 mm jack while holding down or up the volume button on the headphones (in an attempt to counter a possible glitch created when adjusting the volume button while unplugging the headphones), but to no luck.

The issue disappeared for about two weeks for an unidentified reason and restarted recently. The iPod hasn't been plugged in a computer in years so I would exclude any recent virus or malware resulting in this behaviour and thus I doubt reinstalling the "iOS" via iTunes would help in this case. The cable of the headphones seems to be aged to the point where the metal wires inside the cable are segmented as sound will only come from one ear of the headphones and turning the 3.5 mm jack will produce some scratching noise in the headphones (instead of music) leading to the second ear of the headphone to works. I tested rotating the cable with another 3.5 mm jack speakers and confirm that the scratching noise is due to the cable itself of the headphones when rotating it in the 3.5 mm jack of the iPod and not the components of the slot for the 3.5 mm jack on the iPod itself. Also, the screen is cracked on about 40 % of its surface which didn't influence much of the ability to click on it (and tape was put on top of the cracked glass to help prevent losing pieces of it). Lastly, some parts of the glass have gone missing (about 2 mm per 4 mm wide hole) at the bottom right corner of the iPod which led to preventing clicking properly on the screen (see picture below). (The missing part of glass occurred after the volume lowering issue started and thus I would assume that they aren't linked together).

The volume lowering issue seems to occur to other users as threads about this very issue seems a common problem with these devices which surprise me much since its Mac quality.

I would like to know as precisely as possible what is causing the iPod to lower by itself its volume in order to help figure out how to fix such a device. Is it hardware? If so, what electronic component exactly would produce this kind of behaviour? Is this a bug / glitch? If so, how can it be circumvented?

I was thinking that maybe cut wires inside the headphones could lead to this glitch if volume is adjusted via the headphones while the cable is twisted leading in changes in 1, 2 or 0 ears of the headphones working for a fraction of a second and that change of power flux to the iPod could result in creating a glitch where the iPod has no end of the signal for volume adjustment in one or another direction (- or +)?

As the device is quite aged, replacing the glass can be an option, but figuring out what is really causing the volume auto-lowering mode would help into taking appropriate decision for the future of that electronic device and also be interesting into pinpointing the exact cause of the issue (that still remains unidentified on other threads).

Thanks in advance,

Best regards,

B