> For the complete documentation index, see [llms.txt](https://support.audacityteam.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.audacityteam.org/au3/troubleshooting/error-codes/error-9999-unanticipated-host-error.md).

# Error -9999: Unanticipated Host Error

Learn about causes and fixes for this error.

## Causes

This error means "something is wrong", most commonly

* A lost connection to a USB audio device
* Missing microphone permissions from the operating system.
* Your device is unable to playback other tracks while recording.
  * This most commonly happens if you're trying to record at a different sample rate than the device's playback rate. Making sure the sample rate matches in both the Windows Settings and Audacity's **Audio Setup -> Audio Settings** may fix this.
  * Turning off Overdub via **Transport -> Transport Options** may fix this.

## Fixes

You can try the [Common troubleshooting steps](/au3/troubleshooting/common-troubleshooting-steps.md), or attempt any of the other workarounds of this page.

{% hint style="success" %}
If the troubleshooting steps aren't working for you, feel free to ask in our communities:

* [Forum](https://forum.audacityteam.org/)
* [Discord](https://discord.gg/audacity)
  {% endhint %}


---

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