Using YouTube API v3 to tell if a channel has a live stream

The goal of my YouTube API call is, given a channelId, to return whether that channel is currently live streaming. This is the call I'm making currently:

https://www.googleapis.com/youtube/v3/search?part=snippet&channelId={CHANNEL_ID}&eventType=live&type=video&key={YOUR_API_KEY}

While this call is functional, there is a significant delay between the channel starting a live stream and this call returning the stream.

Is there a better call to use in the YouTube v3 API that doesn't require oAuth? The functionality of my app is read-only.

Thanks!