are those speakers powered by an amp right now?
as for the tweets...ive been having that problem for about year....it goes on and off. i tried to isolate that problem by switching the RCA, switching xovers, replacing speaker wires....and rewiring them solved it for me.
since you took it to a shop to get it installed, i say go back there and demand your stuff to be sounding right. you did buy everything brand new.
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