---
title: "stop(IOProcID:)"
framework: Core Audio
role: symbol
role_heading: Instance Method
platforms: [macOS 15.0+]
path: "coreaudio/audiohardwaredevice/stop(ioprocid:)"
---

# stop(IOProcID:)

Stops IO for the given AudioDeviceIOProcID.

## Declaration

```swift
func stop(IOProcID: AudioDeviceIOProcID? = nil) throws
```

## Parameters

- `IOProcID`: The AudioDeviceIOProcID to stop. This can be nil to stop the hardware if a call to start was made with a nil IOProcID.