My issues were very intermittent (more so than what you describe). I could have no issues one day and then several the next. It was very frustrating. I had no issues either with a Bluesound and a much less expensive Cambridge DAC. My issues started when I got the Weiss. I did reach out to Weiss and they got back to me suggesting a firmware upgrade, but that required sending the unit back to them, which I thought was ridiculous. I tried different cables, different types of cables (usb, coax) and a different Weiss and Bluesound.
Like I mentioned, I did fix my issue using the iFi device to essentially “break” the USB, cutting the 5v coming from the Bluesound and replacing it with a much cleaner source of 5v power.
I don’t mind troubleshooting things, but this was sort of ridiculous. Had it not been for truly liking how the Weiss sounds in my system, I definitely would have gotten rid of it. Fortunately now it has works fine and I have since added a ModWright PS as well.