H-K Premium Audio has weak treble?

I just got a 2003 330i... It is, indeed, the Ultimate Driving Machine.

I guess I should now change my username to "2buy". :)

The only thing that has disappointed me so far is the H-K audio system... specifically the high-frequency output. Bass and midrange sounds are wonderful, but the higher pitched sounds seem to be relatively too soft.

I've already tried playing with the treble/bass balances...

Has anyone experienced similar problems? Any proposed solutions?

Thanks.