OnAdFullScreenContentClosed event is trigger delayed after a Video Interstitial is closed

[malt03]

[REQUIRED] Step 1: Describe your environment

• Unity version: 6000.0.26f1
• Google Mobile Ads Unity plugin version: 9.2.1
• Plugin installation method: Unity package manager
• Platform: Any
• Platform OS version: Any
• Any specific devices issue occurs on: it happened in several of our test devices. Pixel, iPhone etc.
• Mediation ad networks used, and their versions: Google Admob

[REQUIRED] Step 2: Describe the problem

Steps to reproduce:

#2029
#2616
The same issue persists, I mentioned as a reference.
OnAdFullScreenContentClosed event is triggered with a delay depending on the device after the video interstitial is closed.

Occurs only in interstitials. It works fine in test ads and using admob test ad units. Occurs only real ads. I'm using Admob mediation and other ad services are fine. It only happens with Admob video interstitial Ads. This issue doesn't happen on all devices. Some devices have issue. For example, the Google Pixel 6a device has a delay of about 1 seconds. I've seen a delay of up to 5 seconds on some low hardware devices.

This problem is quite detrimental to the user experience.

[RubyForest]

same with reward ads is closed

[NVentimiglia]

Thank you for raising awareness on this performance / latency issue on the APIs. This issue will take some time to verify, but we are looking into verifying and fixing any slow APIs.