Greetings,
Upon firing up my mid 2014 Macbook pro running Mojave 10.14.6 the rear outputs on the Quantum do not output sound, even as the meters on both the interface and the Universal Control app show output activity, and the signal is being routed through the headphone outputs. Strangely enough, wiggling the main knob a few times on the interface seems to "wake up" the rear outputs about 80% of the time, while other times I need to reboot everything to get it going. In a seemingly related situation, the main outs sometimes disconnect when the system is left on for an extended period of time and my previous methods must be employed, usually requiring the reboot option. Rarely, everything starts up as it should with no problems. These symptoms are consistent regardless of application: YouTube, Spotify, Logic Pro, and Presonus Notion all respond the same.
Kind Regards