Thanks, that makes sense. Why didn't I think of that. The traces aren't visible in the picture, but given the mystery parts' position on the board they probably are located beteeen the tube output stage and the output jacks in the signal path. If I get serious about buying one I'll send an email asking about them.Interestingly, I looked at the Diy Biz web page this morning and the DAC-38 is still included in the list of offerings, but when you click on it the page that comes up says "There are no products to list in this category". Are they playing games with my head, or is it divine providence delivering me from temptation by removing the source?