Poor phone line

[Coylec]

Wondering if anyone can help me. I upgraded a few weeks ago to an iPhone 8. When on a phone call the person on the other says it’s a bad line and can barely hear me. This has happened with every call. However, if I’m on a call using WiFi or data (e.g. WhatsApp) there’s no issue. Has anyone experienced this?
Thanks

[MI5]

If this is just in one location, it might be a local mast issue?
http://status.o2.co.uk/

[jonsie]

Have you tried cleaning the microphone?

Do you have a case that may be interfering with the microphone?

[Marjo]

Hey @Coylec, I just wanted to check how you're getting on with this and if you ended up finding out what the issue was in the end? Any help from the above suggestions?  

[Coylec · Accepted solution]

Thanks for the suggestions everyone. I’ve discovered when on a phone call, if I change to speakerphone the issue disappears. So it seems like a problem with the microphone. I’ve searched on the internet and this seems to be an ongoing issue with iPhone 8’s. really disappointing as I can’t have a proper conversation on my phone where I’m heard clearly.

[jonsie]

Do you have a nearby Apple store?