Cable burn in

Hi all. I’m guessing that what I’m experiencing is pretty normal. But it can’t hurt to get some feedback. I purchased a DMS-650 from Cary Audio which is a DAC/Streamer. Since hifi folks have highly opinionated views on cables, nothing is included with the unit. So when I set it up, I had to scramble and I found the three conductor cable that came with a cheap Sony DVD player. Then I replaced that RCA interconnect with a much better quality Blue Jeans cable. Initially the increase in quality was apparent and obviously worth it. However the sound could be hasrsh on certain recordings. Various tracks had a harshness that wasn’t there before. I’ve been playing internet radio during the day for burn in. Now that harshness has vanished. Sitting down to listen last night, things were actually too warm. Some tracks sounded almost muddy. The sparkle was diminished in an obvious way. I am guessing that once burn is complete the sound will settle happily in the middle somewhere. Is that a reasonable assumption?  I’m also likely going to order power cables and an interconnect from Audio Envy or maybe some other companies to compare. The guy who sold me the Cary Audio gear is not a salesy guy, but he did pretty emphatically recommend some higher quality cables.