Hi Bogie 1519. I had a similar problem with using the HH version if the Stingray when I first got one in 2007. There are three key things
1) When you use a setting with both pick ups in play (or just the neck) the amount of bass added is such that I find I need no bass boost on the preamp
2) Both pick ups together can produce more scoop in the sound - the mid range needs to be at least at centre detent if nit boosted a touch
3) Make sure the neck pick up is set lower from the strings than the bridge pick up - there are factory settings for these which you can get from the EBMM website. If it’s too close to the strings it will affect the sound.
I find I use my two pick up Stingrays or Sabre basses often. The Stingray Speciajs can produce a very good version of the Bernard Edwards Stingray sound. However I normally use both pick ups in humbucker mode live.
I’ve found that all of the settings on the switch need marginally different EQ settings to get the best sound. I hope you manage to get it to work for you - as someone who owns each variant of Stingray, and bought their first in around 1979, the Stingray Specials are great basses - probably the best Stingrays yet.
This is my other one
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