It can be very frustrating because you have to make sure the type of files that you want to play are compatible with both your player and your DAC. One additional variable is the hand off between the DAC and the player if they are separates.
The CDR experiment was doomed from the start for the reasons that you cited. Most people will play these files from a flash drive or some other hard drive. I also tried using a spare MBA from circa 2009 and it didn’t end well. Macs can be made to play FLAC but it’s a lot of work and you are better off using an Apple Format, another hassle, and the MBA just isn’t a high end player. It also tended to stop playing when an email would come in. A program like Audirvana Plus might solve all of these issues, but it needs a fair amount of computer processing power to work well, and my MBA used to get hung up a lot
@lordmelton hit the nail on the head. Life will be easier if you get a streamer, one that can handle external storage such as a flash drive, and that can handle various resolutions. You could get one without a DAC if it has outputs that are compatible with your DAC. Something from the iFi lineup will probably fit the bill for a few hundred dollars. Obviously try to do a home audition or get a return policy that will allow for the possibility that the player and the DAC don’t play nice