How to resolve FaceTime audio issues with AirPods?

Hi everyone,

I’ve been facing a frustrating issue during FaceTime calls, and I’m not sure whether the problem is on my end or hers.

Issue:

When I FaceTime my girlfriend in Vietnam, she can barely hear me. It’s not about volume — even when I speak loudly and clearly, she only hears a word or two from the entire sentence, like 1% of what I say.

Meanwhile, I can hear her completely fine.

What We’ve Tried:

• Both of us have AirPods (4th gen). We tried FaceTime with and without them — she can only not hear me when I use AirPods.
• I switched to wired earphones — she could hear me clearly then.
• I tested my mic using Siri, Voice Memos, and phone calls — all work fine.
• I FaceTimed other family members — no issues on either side (both her family in Vietnam and mine in the US).
• I tried FaceTime via my Tesla, and she could hear me fine there too.
• Both of us are on iOS 18.5. Everything up to date.
• She has iPhone 14 and mine is 12
• Both of our internet speeds are around 100–300 Mbps (down/up) with ping around 11–30 ms.

Question:

Has anyone experienced FaceTime audio not coming through only for one specific person?

What else can we check on either end? Could this be a compatibility bug or mic routing issue?

Thanks in advance for any help!

[Re-Titled by Moderator]

Original Title: Other Person Can't Hear Me Clearly on FaceTime — Only Catches a Word or Two