I agree, there may be some changes, but they must be very small, or else most of our circuitry would have problems working reliably.
But I do think that there may be something to some claims.
I used to build computers and then attempt to overclock them as a hobby. It has happened to me several times that at some point I increased the clock to the CPU too high, and it would crash. If I then reduced the clock frequency and ran the system doing a CPU intensive task, such as folding or SETI for several hours, I could then increase the clock back to the unstable frequency and the system would operate reliably. Something changed, something happened.
In the hobbyist community I used to frequent there used to be talk of electron migration as a possible explanation, but these discussions were way over my head. I can say for certain that changes happened. A system that before burn in would crash almost immediately would now work reliably for days and weeks after burning in.
Do similar things happen in audio equipment? Do changes happen that would be audible?
The overclocking is purely anecdotal, that's not at all what happens in a chip. Gates, or transistors fill up with electricity, and once they fill to a certain to voltage, the gate transistor either becomes conductive or insulator (hence the transisitor part of it)
Filling up and expulging takes time, and as you speed up the clock past a certain amount, these transistors start behaving erratically. Not all transistors are made equal, so sometimes you fill them up faster, some are filled up slower. This happens in the nano/pico second scale, but at overclocked times it will be affected.
So imagine this, you have 16 billion transistors, and you have the best of the best, meaning the center disk of the silicon wafer, which is usually reserved for the top end chips, you can clock them higher because on average, you have pure transisters that fill up at equal times, and dump at equal times, so when you up the clock speed, there are no errors or run time issues that affect the cpu's performance.
However, you take a chip that's closer to the edge of the wafer, that's full of impurities, the transisters in them aren't equal, some are slower, some are faster, and you clock those up, some transistors don't turn 0->1 fast enough, and cause logic bombs and logic issues (so your program crashes)
What you're saying is, if you run the CPU for a while at low speed, and then clock them faster, suddenly it'll be fine. This is not true, it is almost entirely anecdotal and you didn't do enough testing to figure out why (flip a coin 500 times, you'll get heads in a row for a while)