Short story: what worked for me was to turn off TTS-thing!(talkback)
sounds stupid and basic, but it worked..
I had the same problem after updating my android system this spring, an annoying clicking/scrolling sound in whatever program or window as long as the "media"-sound was on at all, and it has been bothering me ever since. It seemed like for every name, line, program or whatever I was scrolling through, it made a sound. and for every click on an icon, it made another sound. It was really annoying! What was even more bothering was the stupid replies I saw to people experiencing the same problem(few as they seems to be), to:" turn off the touch-sound" or :"go into "settings--> sounds and notifications".." etc, as if that's not the first thing to try.(no offense to those guys, I know they're just trying to be helpful!)
This is when the googeling started, a googeling-session that would last me a lifetime, it would seem.. but it probably was just several hours... of hard work, sweat and beer.. mostly beer.. anyway, so since I couldn't find anyone who had the problem AND a solution, I started experimenting. The first thing would obviously be to take one step back at the time the problem started, by resetting to factory settings --> did not work. Then I tried flashing my sgII and searching for audio-files in the root, much like the fix for the shutter sound, I thought maybe there's also a sound-file for this shitty effect.. there was none.. at least that I could find! The last option was to install a whole new android-ROM, but it seemed like a lot of effort, so I ended up broadening my googleling, and came across a guy that made text-to-speech apps, that would read out whatever you were scrolling through.. sounded interesting and familiar, so I read more and experimented a bit with the TTS-function, and voila.. complete silence..
[settings-> availability->talkback.. maybe, I'm not sure, as my gs2 is in norwegian.. but something like that I guess]
to me it would seem that instead of a functioning TTS-thing when I scrolled or touched an icon, or something else, I got a warped sound. Whether there's a broken link somewhere that connects the wrong sound, or if the sound-file is broken is not for me to find out.. But at last I am free to use my SGII as it was meant to!
hope this is your solution too, if not: I am really sorry!
PS: and hope I did'nt write too long!