M1 Max: Isolated Render Deadlock (3 FPS) with Advanced Scene Switcher (CoreAudio Conflict)
I have isolated a severe performance deadlock on my M1 Max (macOS Sequoia 15.7.8 / OBS build 32.1.2 64-bit Apple Silicon) specifically tied to the Advanced Scene Switcher plugin (v1.34+).
Isolation: I disabled/uninstalled all plugins and activated them one at a time. Advanced Scene Switcher was the only plugin that caused this. At first I had assumed that this couldn't be the problem as I've used this plugin without issue for years. But I tested with a fresh, default configuration of Advanced Scene Switcher. The issue persists in this isolated state.
The Symptom:
- The Trigger: Switching back to any scene that uses a previously active Audio Input Capture (Behringer U-PHORIA).
- The Choke: Performance dives from 60 FPS to ~3 FPS. Render time spikes to 2150ms, while CPU stays at ~3%.
- The "One-Shot" Discovery: I can create 10 unique audio sources for 10 scenes and they all work once. However, the moment I return to a scene I've already visited, the choke happens immediately.
- Inactive State: This happens even if the plugin is set to "Inactive" with no macros enabled and in its freshly. installed state.
The issue only resolves when the plugin is completely removed or unchecked in the Plug-in Manager. Restarting OBS is the only way to "reset" the audio sessions, but the cycle repeats as soon as a source is re-used, which isn't practical, so the only solution I have is to disable the plug-in.
Thanks for all you do on this plug-in. I hope the above helps you find the issue. This only started happening recently, I've been using ASS for years.