In regards to first version BP DAC - which I own and like very much - I've recently been engaged in a discussion with Gary Dews (owner of Border Patrol) about the quality of the driver embedded in the DAC. The version of the BP DAC I own comes with the C-Media CM6631 driver; others are suggesting it should be replaced with the newer, better X-MOS driver. (Gary is willing to change out the USB card in the unit for a fee.)
It has come as a revelation to me that different drivers can have significant (emphasis on significant) impact on sound quality, or at least that's what I'm being told. As there's not been much discussion about this on audio boards so far as I know, I'm interested in others' take on this.
Steve N., any thoughts?