Not sure if this is in the right section,cos i am not sure where the problem lies. i.e.certain notes will resonate/sustain/boom call it whatever,much more than others on my bass. notably the open D or D played on the A string when unamplified.this may change when amplified according to room acoustics to open E or E anywhere on the fingerboard,and sometimes between B to C#. When amplified this creates a feedback situation.Another problem can be my not being able to hear certain notes no matter how i eq the amp/preamp,position the amp or bass or myself in relation to the sound source. This only occurs in one or two places that i play but it can be really annoying and affect the way i play. Are there any tweaks i can make without spending megabucks,to setup,string choice,eq etc. to reduce the effect? thanks.............steve.