I run MC24 v78 on my iMac which is used as the DLNA server. It’s connected through WiFi to my Oppo Sonica DAC source which is connected to the preamp of my 2 channel system. The server configuration now has the Audio output to Original. I had it set to 750 milliseconds and there were long dropouts, 2-3 seconds. In Original the dropouts seem fewer and shorter but still happen. Any suggestions? By the way the Mac has a TB hard drive and 8 GB of RAM. The FLAC files take up about 140GB’s.
Since you can't control the buffering of the server to the Oppo DAC it's up to the DAC to determine how much buffering to do to insure a continuous stream.
You might try right-clicking on the Oppo zone and turning off the DLNA controller option for SetNext.
If that doesn't change anything there is something odd with the network chain between MC and the device.
It's possible you might have a switch or duplex issue.
How exactly does the Mac network to the DAC? (wired/wireless, switch, router, etc)