I am not sure I understand your question, but here are my thoughts:
You need to look at your system as a whole. What you describe would most likely stem from your electronics and from the source material.
If you are happy with the way high frequencies are presented some of the time, but not all the time, the reason its most likely that some of your source material is not that good.
In my experience your cables perform well with a wide range of equipment. However, if this equipment has weaknesses, the cables will not conceal this.
The bass response is heavily room dependent. If you have dominant room modes, the bass will sound loose and have noticeable peaks If your amplifier has poor control, this will also be very audible.
Whichever, the cable is not at fault.
I hope this helps, if not, please feel free to ask more questions.