Hi,

I had few long rehearsals last days and I used my FF800 for loops and VSTs on analog out 1-2, click on 3 and cue on 4. It was simply set in Cubase, and similar in TotalMix (TotalMix Operational mode: Full Mode). The problem was between second and third row in TotalMix.

1. At some point I've heard the loops coming ONLY from right side. So I checked the TotalMix - in the second row the meters showed everything OK - the stereo signal on 1-2, and 3-4 also were correct. So I assumed the Cubase is working perfectly. In the third row Out 1-2 the signal was visible only on the right channel. Both pans knobs were on center and the width was 1.00, there were also no MS Proc etc. (Also it worked OK few minutes before.) At that time I tried to move pan knobs and there was no change (when I panned the 3rd row Analog Out 1-2 hardly left, there was no sound on both 1-2 channels so it appeared to work OK; I don't remember if I also tried panning hardly left the 2nd row pan knob, probably yes). Then, I turned the stereo width on 2nd row Out 1-2 to 0 and the signal started to show in both out channels (I'm not sure if it was only R or L R channels of the loop, it wasn't important for me at that point). I checked the Matrix view and the values were corresponding to the values in Mixer view, but the sound wasn't coming from Out 1.

2. AFAIR there were also other situation when the card stopped to send some of the channels. I remember I needed to reboot the computer, because the click/loop wasn't audible. Of course I checked if reconnecting the interface is enough, AFAIR I checked also rebooting the interface (as it is faster then rebooting the MacBook).

Environment:

The laptop is MacBook Mid 2015 (i7 4870HQ @ 2,5 GHz with some throttle sometimes but NOT so much during the problematic moments, 16 GB DDR3, 2 TB very fast PNY SSD/NVMe; graphic cards Radeon R9 M370X and Iris Pro). It runs Catalina. I used Cubase 8.5 (which has no official support for Catalina, but worked quite well before), the card was running 44,1 kHz with 192 samples latency.

There was a Nord Stage EX connected to the MIDI IN port of RME FF800, but Enable MIDI Control was disabled. Enable OSC Control, Network Remote, etc - same. The Input/Output port of Options -> Settings -> Aux.Devices points to RME MIDI Ports, but the Device Type is None and there's no other option available.

The power adapter of MacBook is unoriginal I think. For now I don't have an original adapter. There were external USB3.0 HDD (2,5"), eLicenser and Thunderbolt adapter connected to the MacBook.

I've checked the system.log but I haven't found anything weird (except for such lines)

Jul 22 18:05:52 macbookkb Cubase 8.5[1026]: assertion failed: 19F101: libxpc.dylib + 92807 [68D433B6-DCFF-385D-8620-F847FB7D4A5A]: 0x89

and LOTS of

Jul 22 18:12:13 macbookkb com.apple.xpc.launchd[1] (com.apple.mdworker.shared.02000000-0300-0000-0000-000000000000[1412]): Service exited due to SIGKILL | sent by mds[141]

I'm trying to repeat the problem at home (the Cubase session has been playing round and round the whole night, on Cubase 10 though, and without the external drive and Nord connected), I even try to work mostly on this MacBook and everything is OK since yesterday (except the CPU throttle sometimes and both fans @ 6k rpm). I plan to run the test this night with higher current load (USB hub, few drives, etc).

What would you suggest to do?