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##

# 3.3.4.12 USB_HOST_AUDIO_V1_FeatureUnitChannelVolumeExists Function

## C

    bool USB_HOST_AUDIO_V1_FeatureUnitChannelVolumeExists(
        USB_HOST_AUDIO_V1_OBJ audioObj,
        USB_HOST_AUDIO_V1_CONTROL_ENTITY_OBJ entityObject,
        uint8_t channel
    );

## Summary

This function returns "true" if volume control exists on the specified channel of the feature unit. Channel 0 indicates master volume control. This function is only applicable to a feature unit. Prior to calling this function the entity object should be obtained by calling USB_HOST_AUDIO_V1_ControlEntityGetFirst, USB_HOST_AUDIO_V1_ControlEntityGetNext, or USB_HOST_AUDIO_V1_EntityObjectGet.

## Parameters

Parameters | Description
audioObj | USB Host Audio v1.0 Device object
entityObject | Audio control entity object
channel | Channel number

## Returns

- true - Volume control exists on the specified channel
- false - Volume control does not exist on the specified channel

## Remarks

None.