> ## Documentation Index
> Fetch the complete documentation index at: https://docs.magicfox.co/llms.txt
> Use this file to discover all available pages before exploring further.

# I'm getting a message about added output latency

Occasionally, you may see the following warning message when you open a MainStage concert:

> This concert contains plug-ins that add output latency. This will cause a longer delay between audio or MIDI input and audio output.

<img src="https://mintcdn.com/magicfox/IQdG2at1jThJh_Be/images/documentation/MainStage-concert-plug-ins-audio-output-latency.png?fit=max&auto=format&n=IQdG2at1jThJh_Be&q=85&s=84009f43615b37d7a37b4d6deaa1a5fc" alt="Main Stage Concert Plug Ins Audio Output Latency Pn" title="Main Stage Concert Plug Ins Audio Output Latency Pn" className="mx-auto" style={{ width:"40%" }} width="260" height="310" data-path="images/documentation/MainStage-concert-plug-ins-audio-output-latency.png" />

**Latency** is the amount of time between when a key is pressed and when the sound is produced. It's possible for a keyboardist to feel a delay with as few as 5 milliseconds, so we try to keep the latency as close to 0 as possible.

Occasionally, we may use a plugin that adds a small amount of latency so MainStage will show this warning message. Because this doesn’t necessarily relate to higher CPU usage, **you can safely ignore this message**.

## Read more

* [Common audio issues in MainStage](/troubleshooting/common-audio-issues)
*
* [Do I need an audio interface for MainStage?](/articles/why-use-an-audio-interface)