I got a new solid-state DAC that was gaining traction in the pro market but not in the home market. I was one of the first home users to buy this DAC. I met the designer of the DAC at a meetup and told him the DAC sounded fatiguing at first and needed about 150 hours on it to sound good. It has a feature to add 2nd order harmonic distortion to "tube it up" a bit. I told the designer I could not listen to the DAC without the 2HD cranked up at first. He was a little horrified at that statement since he discourages using that feature, except for edge cases.
After 150 hours on this DAC, I dropped the 2HD level to a very low number. Now with 1000+ hours on it the 2HD is turned off and the DAC is running ’naked’ as the designer suggests on his web site. However, one difference is that he now burns in the DAC for 150 hours before shipping. I had 2 brand new units to try this with and both had the same result.
A more well know home user DAC which I also love is the Meitner MA3i. I also had 2 of these in the house at separate times. The RJ45 Ethernet input on the MA3i is excruciating to listen to under 50 hours, after 100 it sounds very good. The USB was good right from the start.
Let your ears be the judge.
@ozzy I do not turn on my amp when burning in a preamp + DAC. With my latest DAC it does direct to amp, so I hooked it up to a Class D amp to burn it in.