Just an update on the Bifrost. I finally sprung for the Apple camera kit cable for my iPhone. This allows me to extract the digital when playing itunes which which with a USB type A to type B cable connected to the Bifrost, am getting pretty good sound.
The iPhone will operate like this, but if I connect to the Parasound P5, the phone says it needs to be plugged into the wall for power too. Either way, the sound is spacious, clean and detailed without being bright. I did get an Anker that charges too,
I also added an Audioquest Jitterbug, which cleans up noise related to power in the USB spec. In my system I'd say it does enhance the audio, but it's not a revelation.