Need some treble

Add silver interconnect cables.  Preferably Amadi Cables. Maddie signature silver cable.  Great price and quality  . You will get extended clean highs,  perfect mid-range,  very dynamic and extended bass reproduction.  I hope this helps.  

Ear cups

What are your speakers? 

I'll second Philip's post for Amadi.  Have had several pairs of Amadi Maddie Signature ICs and they show very well in the highs because of the silver wire used. They are also excellent at all frequencies so you would be lacking nothing.  They are also a low to mid cost IC.  

Bob

Get hearing aids and put it on a setting called HIFI