Sinch Voice API: Choosing between v1 and v2
For all new projects, please use Voice API v2. This is especially important for projects involving:

- AI capabilities like Streams and Voice Relay
- Voice campaigns like Batch calling


You should only use the older Voice API v1 if one of the following is a strict requirement:

- The project must be in General Availability (GA).
- The project requires In-App voice or Conferencing (until these features are available in v2).


## StreamControl

Commands that can be executed on an ongoing stream.

#### Payload Schema

- **command** (string)


| Enum value | Description |
|  --- | --- |
| clear | Clears the audio buffer on the Sinch platform. Use this command to discard any buffered audio data that has not yet been played out to the caller. |
| heartbeat | Indicates that the connection is still active. Use this command during periods of silence to prevent timeout and maintain the stream connection. The no-audio timeout is 1 minute. |