I've had my T8 for about 2 weeks now, and have not experienced any lag. However, have you tried changing the output to see if that eliminates the problem? I first set up mine using the I2s output into my PS Audio Directstream DAC. There are eight different modes for the I2s output on the T8. I figured that one would work, and the others would just put out static or no sound at all, like the I2s output on my NuPrime CDT. So when I connected it, it defaulted to Mode 1 and I figured that I was just lucky to have hit on the correct connection. I sat down to do some critical listening, using a few tracks with which I am familiar, and was shocked that the imaging was terrible. The instruments were not in the correct positions; even worse, they would seem to move around. The cello in a Beethoven string quartet was in the center of the stage, when it should have been stage right. At a couple of points, it moved to stage left, and then back to center. I continued to test the unit for a couple of days hoping that burn in would solve the problem, but it didn't. Since soundstage and imaging is my hot button, I was going to send the unit back. Then I decided to try a different output to see if it was just the I2s connection. Since I had a good quality XLR cable, I tried that output, and problem was resolved. So I went back to the I2s output, and tried the different modes. Turns out they all put out sound, but not necessarily correctly. Finally found that Mode 5 was the correct mode, and that not only solved the problem, but detail, soundstage, and imaging were all correct and improved, even better than the XLR output.
I bought the T8 to replace a Node 2i moded with a Teddy Pardo LPS. The SQ is definitely better, but not by orders of magnitude. Everything is improved noticeably, soundstage, detail, imaging, bass. Not as great as improvement, however, is when I changed out the power supply on the Node 2i; that was a "holy crap" improvement! Improvement is enough that I am keeping the unit, and have installed it into my rack. OS is just as good as BluOS, just a little different. And it supports the streaming services I use most, Idagio and Amazon Music HD.