Just for info, been having issues of random stopping of playback with macOS Sequoia since Sequoia Beta 8 and the RC. Issues were associated with the network subsystem and problems with 3rd party security suites. Appears some late changes to the Sequoia networking subsystem has led to issues for quite a few people. For me, submitted a bug report as I logged a network error in Beta 8 that was causing AS to terminate playback, to be fair it is very infrequent. Seems they did not fix it even though the issue with packet errors was reported by many people. Link to article below, Apple is apparently aware of the issue and is working on a fix.
Symptoms for me are 1) Playback termination followed sometimes by, 2) subsequent loss of internet connection despite the internet connection being fine on all other devices connected on the network and in a worst case loss of UPnP devices from AS playback options and sometimes a crash of AS.
Pretty certain from network logs that macOS is the cause, have tried turning off macOS firewall as a suggested solution on forums however if it is your only firewall then probably not an advisable solution.
Maybe a good idea if you have not upgraded but are thinking of doing to hold off until 15.0.1 at least.
Info provided by a friend a couple of days ago, that may assist with some issues:
I just spent hours trying to figure out why I could not access a local server on my network using Chrome from just one computer after upgrading to the latest MacOS Sequoia. If you run into something similar, there’s a new feature in Privacy and Security called “Local Network Access,” and you have to grant it to each app individually. It was off for my Chromium-based browsers (ARC and Brave).
Yes access to certain apps in Sequoia sometimes are not enabled in the Privacy-Security/Local Network settings, after getting a prompt to allow Audirvana access to devices on the local network on my mac it was still set to off on one occasion during the beta phase but have not seen this issue in the final version.
I notice quite a few users on Roon having issues (larger user base so to be expected), also people using Firefox, Chrome and some NAS users. For me it is a couple of times a day where a drop out in playback is followed sometimes by a trashing of several network services on my Mac with resulting mayhem in AS, Once the UPnP devices disappear in AS as a result of this issue I have found turning off Audirvana access to the local network in system settings then turning back on does the trick quickly.
May downgrade to Sonoma… trying to summon the energy to download an iPSW of 14.6.1 and do a clean install…To be quite honest the additional features that may be useful will only start appearing at 15.1 and beyond. The outward facing improvments in 15.0 are pretty minimal and to add to this a networking issue begs the question is it worth it at this time…
My reluctance to update straight away over the past 3 years or so, was actually bought on by automatic updates in Roon and the resultant havoc. But Roon is long gone……
Was going to wait with Mac sequoia anyway and I only updated Studio today after seeing no reports of issues the few days.
Good luck with your reinstall. A braver man than me.
A salient question: “How does Audirvana behave running on Sequoia with a DAC connected via USB?”
It seems once again, the complexities of network connectivity interfere with the equanimity of playback, as compared to simple USB-based transmission to the DAC…
However, I do see where one of my plug-ins designers (Eventide) is warning not to upgrade until they verify reliable operations and/or they adapt the applications to this macOS…
No issues with USB whatsoever. It is changes in the network stack that occurred late in the Beta process, beta 8 and RC, that is causing the issues. For me if the macOS inbuilt firewall is turned on I have major issues with not just Audirvana in terms of networking services being lost.
I have turned off the firewall in macOS and reverted to installing Intego NetBarrier as a firewall and the issues have stopped for the last 24 hrs. Will see if that continues.
The macOS firewall is off by default. Apple assumes people use their Mac’s on private networks so probably not a massively widespread issue. Early days in the diagnosis of the root cause will see what Apple does this week.
Update
Since turning off the macOS Sequoia inbuilt firewall my system has run without issues for 48 hrs. Audirvana working as normal, playback 100% uptime with zero issues. Problem therefore seems to be in the Internal Filewall or at a lower level in the network stack which is triggered by the Firewall. Lesson therefore is if you update to Sequoia do not turn on the macOS firewall option in system settings/network until Apple confirms issues are fixed.
A braver man than me. 
