Not loud enough

SOURCE: I have a cect i9+++ buzzing noise

This problem exists actually at all phones of this kind. The microphone replaced to a more sensitive type, but the firmware is not tuned for it. In this case, the electromagnetic field of the flash memory controller near the microphone generate this noise. If you pull out the mic from its case, the noise clams up immediately. This problem could be solved by a new firmware. The voulme of the microphone can not be adjusted through the phone's UI.

SOURCE: makes a terrible loud noise. It hurts my ears.

time to check your filters
if you bought it used check your hoses also
some people think sunp pump hose is just like vacume hose but man does it whistle (almost enought to pop your ears loud )

SOURCE: (orignal game boy) no sound from speaker but rattling

i guess your speakers are not recognizing the ''treble'' sounds !
this case, the only solution is buying a new speaker =/

SOURCE: my ipod crackles and my hearing seems to be getting damaged

Id say you should go see a doctor. But for now id say that you should do your best to not listen to it for a while as it can affect hearing. try to use full on speakers if you can. On you tube there are a few Sub-Woofer sound tests you can do. Try playing one (low volume) and repeat. (not a song one) 

http://www.teenbuzz.org/ also to hear which frequencies are out of range to you click here. ( click the second icon on the list further down the page)

But yeah go see a doctor. Perhaps some ear drops.

SOURCE: one ear bud does not have full sound

This is caused by microscopic wax build up in one ear. You'll probably have to send the earphones to Shure for replacement.