Simon Phillips drum content loses right channel audio

Hello all,

Strange problem. I’ve been using Simon Phillips Studio Drums for the last couple of projects. In both projects, after working for a couple of days on building up drum tracks and adding other MIDI or audio tracks, Groove Agent suddenly loses the right channel output. Absolutely zero output. I’ve only seen this issue when using the SPSD content; Not with other drum content, e.g. Allen Morgan, Fusion, Jazz sets.

I’ve gone through the entire signal chain within Groove Agent. The Agent Mixer screen shows stereo output but looking at the kit and master mixer screens show only left channel output. See screen shot pics.

I can’t figure out where the problem could be. What’s more odd is that the problem didn’t start while working in Groove Agent. I was in the process of recording some audio tracks and playing them back when the issue started. Start/stop Cubase, reboot the PC, issue still remains. The first time this happened, I got around the issue by loading another kit and routing the drum tracks to it instead of the first kit I was using.

Since this is the 2nd time the problem has happened, I’m wondering if there is a bug in the Simon Phillips Studio Drums content. Anyone have an idea on how to troubleshoot this or heard of this problem before??

Many thanks,
GrooveAgent-Master Mixer.jpg
GrooveAgent-Kit Mixer.jpg
GrooveAgent-Agent Mixer.jpg


I removed the Simon Phillips drum kit from the Groove Agent 4 SE slot and then replaced it with one of the default GA4 drum kits and the problem persisted. No right channel audio from Groove Agent SE. I think that shoots a hole my theory about the Simon Phillips drum content.

So, I copied the Cubase midi drum track and deleted the original problematic drum track in Cubase. Then I added a new midi track with Groove Agent 4 (not SE) and load up another drum patch. I now have left and right audio channels again from Groove Agent. I worked on the track for about 5 hours and every thing worked fine.

So now, I have seen this issue in both Groove Agent 4 and GA SE 4 with different drum sound content. What’s so frustrating is that I can clearly see in the mixer section (master) that I’m not getting any right channel but in the kit mixer both right and left channels show output. Where’s the control or function point that would cause the right channel to be muted between the kit mixer and the master mixer?? I adjusted the pan controls but it makes no difference.


please try to send MIDI Controller CC10 (Pan) to the left panned GA4 instance.
Just insert a “MIDI Control” modul in Inspectors “MIDI Insert Effects”
There you should change one of the given CC´s to CC10 (Pan).
This should solve the problem.

This issue might be introduced by accidentially sending MIDI CC 10 from your MIDI keyboard