I have a 1996 Maxima and i got a sound system installed(2 12s, new head unit, new speakers) about a year and a half ago. I dont really remember when it started making this noise but every time i accelerate a high pitch wistle sounds comes from the dash/head unit area. Someone told me something might be messed up with my head unit so i was wondering if anyone knows what is wrong or if they know how to fix it. Thanks.