Hi. I just bought American Standard Jazz Bass 1999 4 strings in mint condition. When i came home and plug this jazz bass into amp i play it for a few minuts. All strings sounds good(strings old) and tunes very well, but my E string sounds vibrated(like with vibrato effect) at 12 and after 12 fret. I change strings, change pickup height, setup set properly but problem not gone Please help me, i have only 1 bass guitar((( and can't afford another, any help will be appreciated.