Glitches when playing with USB DAC

Dear all,

I have just updated Volumio on my Tinkerpad from a version installed in May to the build of Nov 20th, 2020 (2.853)
With this update I experience random glitches when playing with my external USB DAC, that has always worked perfectly so far with Volumio.
The glitches manifest list very brief interruptions (order of 0.1 seconds), but enough to be heard and annoying.
Funnily enough they do no happen when listening through the output jack of the Tinkerpad, but only when using the USB DAC. In a case of a wav file sampled at 16bit/48KHz, the reproduction went smooth for the first 80 seconds and then I experienced a glitch and after 20 seconds or so a few more separated by few seconds each, and then smooth till the end of the song.
To stress the system I have used also wav files sampled at 16bit/192KHz and DSD64 and DSD128, which seemed to trigger more glitches.
My files are on a USB stick (class 10), so file reading shares the USB bus with the DAC.
Can this be the result of the USB bus being somehow overwhelmed?
And if so, why was this problem not occurring in the build of May I had before the update of yesterday?

Thanks in advance for any idea.

The problem seem to have disappeared by itself, more on this post below