I mostly ask as a curiosity, since I'm not noticing any other "negative" effects.
Recently I found that my PS4 no longer makes the audible "beep" noise when coming out of Rest mode. I assume this also applies to turning on (I'm just not able to test at the moment).
Don't get me wrong, I'm definitely not complaining at all.
I read through the last few update notes (I update pretty regularly) and didn't see anything mentioned. There are other posts online that have the same issue, usually just a broken speaker, which I figure is probably the issue here as well. Doesn't hurt to double check though.
My disc drive has begun acting finicky as well, so I figure I'm just seeing some symptoms of an aging system start to crop up.