You're going to need some way of getting the FLAC files off the USB hard drive/flash drive whatever you have them on unless you have them on your computer and connect your computer to the DAC.
Hi-end Audiophile grade USB switches
Looking for guidance on which companies make any ultra high quality USB A to B switches in the market place and anyone's experience with them. I need to be able to choose between two different USB sources outputting into one USB input on my DAC. Need one that imparts virtually zero signal degradation and without any sonic thumps when switching between USB input sources. Thanx! Mooncrikit