After upgrading my MacMini i7 to Mojave I experience playback stalls about once per album. Pressing play resumes playback.
This has been an issue from initial Mojave - now updated with Combo update 10.14.3.
The next time this issue occurs, please respond to this thread with the local time at which you encountered the issue. I will then enable diagnostics on the account and request a set of diagnostic logs from your Core. I will then pass the diagnostic logs to the QA team for further analysis.