I bought 4,5 months old RP-600M and Dynaudio Stand 6
I have tested at home with a cheap audio cable, the result not so bright. I find this speakers not enough sub, so I should buy a good sub anyway.
The sounds is really loud, but for me not enough exhaustive. Not enough details in music's.
Maybe the cable, or the AV not enough?
I hoped this Klipsch would be enough clear and detail, but not.
I would try with another cable. Maybe buy a bi-ware cable for future?
Have you put your receiver in to Direct mode? Try to find that.
There is few things you could try perhaps. Make sure you have the speakers about same distance apart as the distance to them. Spread them apart good amount at least 1,8meters and more if you sit further away. Try angling the speakers directly toward your ears if they shoot straight now. Also push them more out if they are close to your front wall cause that will boost the bass but it can make the sound muddy.
So in short: Leave ~30cm behind speakers if you can and spread them apart ~2meter (same amount from tv each side) , angle them toward you so the tweeters points your ears. This should make them sound little brighter.
Make sure the receiver is in Direct / Pure Direct mode so there is no bass boost or other silly features On. Edit. "ANALOGUE STEREO DIRECT" FROM YOUR REMOTE
If you have some basic 2,5mm2 / AWG 14 thick speaker cable then you are good. Make sure Red goes to Plus and Black to Minus in speaker and receiver side (make sure the metal ring is intact it connects to HF and LF)
Connected like this: