No Improvement With Transparent Reference RCA Interconnects For Naim NDX 2 Streamer


I am in need of some guidance from those more audiophile educated than myself. I recently upgraded my 18-old system. My system now is: Mark Levinson 5805, Naim NDX 2 streamer with Naim XPS DR power source, Naim Uniti Core CD ripper to WAV files, and Transparent Super speaker cables.
I use the streamer mostly for music from Tidal and the Uniti Core. My dealer talked me into buying a pair Transparent Reference RCA Interconnects saying my system was good enough to benefit from the $3200 upgrade. After ~ 600 hours "burn-in" time, I have to say that the Refs don't sound any better than my 18-year old Transparent Supers. Transparent's VP even called me when I politely complained, explained how the Refs were tuned for the source impedance and suggested that my speakers may need to be re-positioned to which I replied that there is not much more room for adjustment.
I am wondering several things: if the Refs are simply overkill for Naim's mid-level streamer, or if Transparent "tuned" the boxes incorrectly, or if the Ultras would be better, or if a different brand of interconnects would be better, or fill in the blank.
Your thoughts would be greatly appreciated.
paulg24
A dealer should be assisting you in achieving better sound,  That's what they're supposed to be there for.  I would talk to your dealer about your issues and they should help you.  A customer that spends 3k+ on interconnects is a valuable commodity and your dealer should take your issues seriously.  If not, find someone else. 
Paul, I wish you did not wait for 600 hours for break in.  I would think 24 hours or less would have given you their basic sound signature, anything from there being subtle.  I hope your dealer gives you a decent refund on these now used cables.
Thank you everyone for all your responses. I emailed Transparent sometime ago and I believe their response was their products 70 to 100 hours of break in time, sometimes longer. I also emailed my dealer sales person and he said up to 800 hours. So, that’s why I gave it so long. I am taking the cables back out to the dealer today, either for a refund or to give Transparent another chance to so-called re-tune the cables. 
paul, just my opinion, I would get out from under these cables and just ask for a refund.  Not because of the brand, as I have never heard a Transparent cable, but even if the tuning was off, how much better can they be?