Noticeable video delay when connecting to laptop and DSLR + external mic

Question

I have a Canon EOS RP DSLR camera that is connected to the adapter through the battery, and plugged into a Pengo HDMI capture device, which is plugged into a USB hub (contains 16 USB ports), plugged into a MacBook Pro (new, M1). I also have the Rode NTG1 shotgun mic plugged into a Rode AI-1 USB Audio Interface, also plugged into the hub.

• Pengo HDMI Capture Device
• Canon DC Coupler DR-E18
• Canon AC Adapter AC-E6N
• Mini HDMI to HDMI Cable
• USB hub

I open Zoom app and everything appears to be working:

1. I can see input coming from my Rode mic.
2. I can see my video coming from my Canon DSLR.

However, when I press record, the video is delayed by as much as 0.5-1 seconds from the audio. What am I doing wrong? How do I get rid of all audio delay?

I thought it might be a "Zoom app thing", so I tried recording with the Screenshot app built into Mac (recording my video in zoom playing), and still I get audio delay though a different amount. If I remove the video from the DSLR and use the built-in FaceTime webcam, there is almost no audio delay but still a slight amount.

Should I be plugging the Mic into the camera somehow instead? How do I get everything to sound/play in sync for live streaming or recording?

Using something like OBS to delay the audio to match the video I think is not an option, unless that is the only option haha. I would rather avoid having any delay at all. Why is the video even delaying given this system?

Answer 1

You're using two separate systems in parallel, which have no way to communicate timing info to each other. There's some delay on the video side, and some delay on the audio side, both pre- and post-USB, and the Mac has no idea how to put them back together. Normally, two-system sound setups are genlocked together to keep their internal clocks synchronized.

To fix your issue, instead of using a USB microphone, plug in an analogue microphone into the camera's microphone input. The specs for the HDMI capture device say it's capable of capturing 48khz audio along with the video signal. This way, the synchronization happens inside the camera, and picture and sound are locked before any other device performs processing.

You might need to configure the audio input in MacOS System Preferences->Sound->Input to switch from the laptop's internal microphone to the Pengo capture device.