Re: Buzz in a Sax
Oil all of the rollers, tighten all of the keyguard and brace (bell to body) screws, and use thread locker or plumber's teflon tape to make sure the adjustable height screws on the keyguards aren't loose in their threads, same with the screws on the asjustment bar that closes the G# when the right hand is down, though be careful with that one because it's a very critical adjustment screw and can cause a lot of playability issues if it's put back in the wrong place.
Also, make sure the keywork of the sax has been oiled. Another thing may be to put a drop of oil where each needle spring meets the spring saddle on the key. Basically, oil any place that is metal on metal, but don't over due it with the oil. Less is more and you don't want to end up with a slippery sax!
Then a buzz on the high A may be caused by improper key height of the octave key, play the A and have a friend lift the key a little higher. If the buzz goes away then have a tech open up the keyheight a little.