The recoil spring assembly (RSA) only stays seated in the notch until the pistol is fully assembled; then the rear edge comes out of the notch and rests on another part. During disassembly, it is caught by the same notch as you take the slide off the frame, but it will always be slightly out-of-place (not fully seated in the half-moon notch) when you take the pistol apart (this is normal). However, you should ALWAYS make sure the rim is fully seated back into the half-moon notch during reassembly, or it may catch on another part when the slide is placed onto the frame, and damage the rim of the RSA. This happens quite a bit, in my experience; folks take the slide off, look at it briefly to check something, and put it back on without seating the RSA fully into the notch, and then the rim of the RSA gets nicked/burred/chipped.
If spring-related noises have become much more noticeable after firing than they were when the gun was new, check the RSA for damage, and replace it if necessary. Unless the some part of the RSA is actually catching on another part (slowing/stopping the slide's forward motion), or you are finding plastic scrapings/chips inside the pistol, then a slight increase in spring noise doesn't necessarily mean you have a problem. Remember, the pistol's slide is not intended to be operated slowly, with one ear carefully listening for weird noises. It's designed to slam back and forth at a high rate of speed, ejecting empty cases and scooping new cartridges out of the magazine and up the ramp into the chamber. As long as it's doing that correctly, you should be good-to-go.