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# My controller freezes when I connect my Aux switch to the Omniport

### Problem
When an external Aux Switch is connected to the Omniport, the MIDI controller becomes unresponsive or appears to freeze. The controller returns to normal operation once the Aux Switch is disconnected.

### Cause
This issue may occur if the connected Aux Switch uses a **Normally Closed (NC)** switch instead of a **Normally Open (NO)** switch.
Morningstar MIDI controllers require **Normally Open (NO)** switches for use with the Omniports.
The difference between the two switch types is:
* **Normally Open (NO):** The switch circuit is open when the switch is not pressed and closes when pressed.
* **Normally Closed (NC):** The switch circuit is closed when the switch is not pressed and opens when pressed.

When a Normally Closed switch is connected, the MIDI controller interprets it as a switch that is being continuously pressed. This can cause the controller to become unresponsive, making it appear as though it has frozen.

### Solution
1. **Disconnect the Aux Switch** from the Omniport. The controller should immediately return to normal operation.
2. **Check the switch type** of your external Aux Switch to determine whether it uses Normally Open (NO) or Normally Closed (NC) contacts.
3. **Use a Normally Open (NO) Aux Switch** with your Morningstar MIDI controller.
If your Aux Switch supports configurable switch polarity or NO/NC operation, set it to **Normally Open (NO)**.

### Does this mean my controller is faulty?
No. If your controller returns to normal operation immediately after disconnecting the Aux Switch, the issue is likely caused by an incompatible switch type rather than a fault with the controller.
Using a compatible Normally Open Aux Switch should resolve the issue.