When you connect your iPad to a video capture card via HDMI, iOS automatically routes both video and audio through the HDMI output, as it prioritizes external devices for media playback.
This means that, by default, audio will not play through the iPad's internal speakers or connected earphones when an HDMI connection is active.
To redirect audio to your preferred output, you can manually select the desired audio device by swiping down to access the Control Center, tapping the AirPlay icon, and choosing your iPad's speakers or connected headphones.
However, it's important to note that some apps may still default to HDMI audio, and certain iPad models might not allow audio routing to the headphone jack while HDMI is connected.
In such cases, using Bluetooth headphones or a multiport adapter that supports simultaneous HDMI and audio output can serve as effective workarounds.