AirPod Pros - Bad/Distorted feedback of your own voice when speaking

I have an issue with my left ear AirPod Pro - the right ear AirPod does not have these issues.

When I am talking I can hear my own voice in my ear but it is loud and badly distorted, almost like the speaker playing my voice is blown.

If I shake my head the AirPod makes a noise.

If I tap the AirPod it makes a noise like there is something loose inside.

When playing music the noise when I shake my head and tap the AirPod are still happening, but they don't appear to be a problem in normal mode, only noticeable in Noise Cancellation and Transparency.

This is the second pair of AirPod Pros I have had.

The first pair I had I noticed this problem after approximately 4 months and they were replaced in store. The second pair I have now had for 3 months and I have just started to notice the same problem.

I'm a bit confused as I've not heard of this problem before and is strange that I am experiencing it with my second pair of headphones.

Writing to see if anyone has any advice or has experienced a similar problem.

Thanks.