Speakers sound too bright.

Run the lumin in dsd mode that sounds warmer 

"Ignore the app. Make sure the amp’s positive (red) terminal is connected to the speaker’s positive terminal and the amp’s negative (black) terminal to the speaker’s negative terminal. On both speakers. If one speaker was connected backwards, the bass is out of phase and will cancel out."

Maybe not. Maybe the app is correct and one of the speakers has reversed magnetism? This does happen and I have a professional JBL woofer like this which is reported by one of their authorized service reps as happening for about 1 in 50 woofers!

I just couldn’t get the two woofers to phase properly when connected the same. I discovered that when a compass is held up to the front of the two woofers, one shows north and the other shows south! YEAH THEY DO!!!

Or maybe the wires are crossed inside the cabinet and the external connection would appear correct?

A 1.5 volt battery is probably the best way to check.

To rule out a speaker being wired incorrectly internally and assuming you have your speakers hooked up correctly, just play tracks 22 and 25 from this — no need to mess with resistors and such. Left should be left, center should be center, and right should be right and if all that lines up your phase is fine. I continue to think it’s break in, but you should consult your dealer to get their thoughts as well.

http://www.youtube.com/playlist?list=OLAK5uy_ndrls3SVVIl_vwa6lSQILyH7DnQGCevqg

While checking internal and external wiring for correct phase is always a good check (noting internal wiring checks a difficult task that may void warranty) and out of phase wiring will potentially cancel or reduce bass output, cause potential, perceived brightness due to lack of base, it also produces a characteristic hollow sound and incorrectly wide staging effects.  I recommend you check but do not consider this a probable root cause if you are not hearing the characteristic hollow sound and staging effects.  

If you had speakers in the same room that sounded good to you, return the speakers.  I had the same issue with B&W 702 S2 towers.  The dealer told me to burn them in for 100 hours.  4 days later they sounded the same.  I returned them.  Life is too short.  A lot of good speakers available that will sound good to you in your room.  Suggest buying from a dealer or direct from manufacturers that will let you buy, try and return if necessary.