Audio switch question

I appreciate your very full and helpful reply, but I do think that "a hundred plus" is rather overstating the case. For example, I found this:

I wonder how that volume control is wired so that it works in either direction while still maintaining reasonably high impedances?

nib

I sit at my computer. The headphones stay plugged into the front of the PC. The rear goes to my hifi at the far end of the room, and the HiFi's mains plug comes back to a multiblock adjacent to my chair. I plug and unplug this mains lead when using the HiFi rather than pull out/plug in the rear-panel audio lead. A mains plug can handle more plug/pull events than a 3.5mm jack.

Lean Engineering - achieving the most with the least

Isn't that a paraphrase of the Victorian definition of an Engineer?

Someone who can do for three pence, what any fool can do for a shilling[1].

It is my paraphrase of George Stephenson's words.

The figures I usually use are "five bob" and a "tenner"!

From the days when a common expression was "Spark plugs cost five bob - though they only cost pennies [old pence / d] to make," PA

As I posted a few days ago, I found this switch:

And as a pleasing bonus, the switch nicely matches the small amp which powers the PC speakers.

Thanks to everyone who contributed thoughts and ideas, and apologies for abandoning the ethos of the group and not going for a DIY solution.

Neat, Didn't know such a device existed. Well done in sourcing it

Thanks. I'm very pleased with it: the build quality is excellent (metal case and knobs, decent sockets), there are no problems with the audio, and it has a bit of heft to it.