MIDI Loop Detected - IAC Bussing

Question

MIDI Loop Detected - IAC Bussing

I cannot figure this one out... MainStage patch with one External Instrument channel strip. AMS set for one IAC bus. Logic with one channel strip looking at the IAC bus. Playing the keyboard through MainStage does what I expect - it triggers the Logic channel strip. However - if I add a sustain control in MainStage, as soon as I hit the sustain pedal, BAM! - MIDI Loop Detected. I am stumped. Even with Logic not running, I get the loop. It's as if something about the sustain control is sending AND listening to the IAC bus. But the keyboard control does not behave that way. Any ideas very much appreciated. Thanks.

17" MBP (Early 2011), Mac OS X (10.6.6), 2.3GHz/8GB/512GB SSD

Posted on Mar 10, 2011 7:36 AM

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Answer 1

dhjdhj

Level 2

194 points

Mar 10, 2011 11:00 AM in response to Hans Tobeason

I was about to start my own thread on this MIDI loop issue but thought I'd put it here in case they're related.
I have a very simple concert setup (and I have the IAC device disabled). I am playing an Eigenharp and MIDI in from the Eigenharp is being received both directly by MainStage (on one channel strip) and also by a MaxMSP patch.

MainStage, on another channel strip, is receiving the MIDI output from the MaxMSP patch.

I can play my song 10 times in a row with no problem. Then on the 11th time (say), in the middle of the song, MainStage will just popup the **** MIDI Loop Detected message and everything stops until I press enter at which point it's business as usual.

Because this is completely random, I have no idea whether this will happen the first time or the 10th time. I'm supposed to be performing in public tonight with this setup and I'm just petrified by this issue.

There are no MIDI cycles (of which I'm aware) and I'm actually skeptical whether the actual problem is a MIDI loop or something else.

Anyone have ANY idea how to kill this?

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Answer 2

Romu-lus

Level 1

0 points

Jul 30, 2012 8:55 PM in response to dhjdhj

I have this "midi loop detected error" too.... any luck finding a solution fellas?

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Answer 3

dhjdhj

Level 2

194 points

Aug 4, 2012 5:52 AM in response to Romu-lus

I gave up on Mainstage soon after that issue and switched to a custom-built solution built with MaxMSP. I've used this at many events and will be using it next week at a major gig at BB King in NYC. I sometimes think about trying MainStage again, as new releases come out but my own environment now has much more functionality at this point so it's not worth it.

I just read that the latest version of Mainstage as a new "feature" to block unwanted controller messages. Perhaps someday they will fix the midi loop bug and call that a new feature as well!

At the very least MainStage should tell you WHERE is the loop.

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Answer 4

Yabut

Level 1

8 points

Jul 12, 2013 5:03 PM in response to Hans Tobeason

I've been running into this issue and I've discovered that Logic is reading back the IAC input and spitting it back out again thus the MIDI loop is not coming from Mainstage but Logic. Mainstage is just decting the loop whereas Logic is not.

Here is the solution for this:

http://www.csounds.com/node/234

Basically you need to open the enrivonment window, go into clicks and ports, create a blank object (doesn't matter whichm I just created a monitor object) and connect the IAC output to this object's input. This will remove the IAC return from the SUM input and thus stop the feedback loop.

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Answer 5

micdim

Level 2

199 points

Oct 15, 2013 10:13 AM in response to Yabut

Hi Yabut,

Just letting you know your link doesn't exist. Can you post it again? Maybe wrong URL?

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