Common audio issues in MainStage
No audio
If MainStage is receiving MIDI but the onscreen keyboard keys don’t move, you may need to assign the onscreen keyboard to your physical keyboard.
If MainStage is receiving MIDI but still isn’t producing sound, you may need to set your audio output to your interface, adjust the output or Master fader in the channel strips workspace, or disable the Master Mute by choosing Action > Master Mute or pressing the toggle button on the toolbar.
Clicks or pops
Your computer may have insufficient RAM. We recommend that your computer have at least 16 GB of RAM.
Confirm that the Sample Rate matches the setting on your audio interface. Review your audio settings and experiment with increasing the I/O buffer size.
Hanging notes
A note might continue to play after the key has been released. Press P on your computer keyboard, the highest note on the keyboard, or the onscreen Panic button. Panic immediately silences all sounds and resets MIDI.
If this seems to be more than a rare occurrence, it is most likely caused by a faulty USB-MIDI adapter or cable. Try using a different MIDI cable or audio interface. Alternatively, your keyboard’s physical key contacts may have gotten dirty and need to be cleaned.
Incorrect pitch
If your entire concert is playing at the wrong pitch, choose File > Concert Settings. Under the MIDI tab, ensure that Transpose Concert is set to 0. Under the Tuning tab, ensure that method is set to Equal Tempered Tuning.
Choose MainStage > Settings > General... and ensure that the Tuning parameter is set correctly (440.0 Hz is the default).
Also in the MainStage settings under the Audio tab (MainStage > Settings > Audio...), ensure that the Sample Rate matches the setting on your audio interface (this should usually be 44.1 kHz).
All of the patches play the wrong instrument
If the patches in your concert are playing the wrong sounds, this is usually caused by opening more than one MainStage concert at once. (This has been an infamous bug in MainStage for a very long time). Never open more than one concert file at a time.
There is no simple way to solve this problem because the concert itself is likely corrupted. The easiest solution is to delete the corrupted concert file and re-download a new copy.