I should add, and I'm sure if I say this incorrectly someone will chime in with why, and how and I'll learn something I didn't know...
In order for a DAC to store the bit stream in a buffer, the protocols required to do so have to be processed by a computer. To do a checksum for example, registers (or data storage) need to set aside to evaluate and store information about the packets in order to determine whether or not the packets of data arrived correctly. So the DAC requires an onboard computer to store the data into RAM, evaluate the incoming bit stream to ensure it's correctly read in, or request the data rate is slowed down and data resent.
The bitstream is evaluated from raising and lowering voltage, or light intensity from one device, and measured on the receiving device, if it's either not sent with a very clean signal, the measuring of that signal may be wrong, and if there's no computer to evaluate the data packets it's discarded at best, or becomes corrupted.
We can read written language and within the contxt of the sentnce detrmine the meening of what was written, a DAC cannot.
The least dropouts of data packets, and the less electrical noise, a more accurate representation of the recording, created by transforming a series of voltage changes or light pulses into an alternating electrical signal that can be transformed by a
electroacoustic transducer
(speaker) into sound waves, the better. (Read that aloud three times without taking a breath, I'll have you put in a circus)
Memorial Day - Lest we Forget.