Is my speaker/tweeter blown?

A few months ago I replaced my head unit (stock to Kenwood Excelon KDC-X494) and all four speakers (stock to Kicker KS680's). They have been running good up until now, my front right speaker (passenger door) makes a weird hissing-ish harmonic noise when on a little higher volume, the rest of the speakers do not. This sound only happens following and during a high pitched noise like the beginning of Metallica's 'Wherever I May Roam' sitar intro and other songs that have something like that. You can also here the hissing hshshssh sound during songs, almost like a background noise, but it's clearly there. Is my speaker's tweeter blown? I did sound checks on all the others by doing balance and fader to single out each speaker, all but this one check out. Thanks!