Anyone have experience with a Schiit Wyrd decrapifier?

Elizabeth - Thank you, I will definitely do a search on that. I have other Mac's in the house.. so I can devote this mac to music playback.

Does email and text messaging interfere?

are you losing connection with anything else or just those two devices?

Just those 2 devices.
My MAC looses connection with my DAC causing me to have to restart devices. I've always had this problem occasionally.. I also have Bit Perfect running if that has any effect. I was wondering if noise from my Mac through the USB cable might be to blame?

After reading up on the Schiit Wyrd, it just may do the trick; however:

What USB cable do you have connected? I had a similar issue with my MacBook Pro connected to a Focusrite Scarlett 2i2 audio interface; (essentially a DAC, albeit Pro Audio). Disconnecting / reconnecting the USB cable would re-establish connectivity; but I don't have to restart. Connectivity issues were reduced when I obtained a better quality USB cable; but it did not eliminate the issue completely.

I do have to state, though, that connection of my MacBook Pro via USB to my Oppo BDP-105 has no connectivity issues whatsoever. Of course, its an Audiophile (Oppo) vss Pro Audio (Scarlett) comparison.

Oh, and just a thought: have you checked your Audio MIDI Setup? Maybe the Clock Source?