I tried multiple things to diagnose this issue, without much success. I also posted this in another thread, but will post it here for increased visibility to users.
I have a 2022 Leaf, SV Plus, just got it a few days ago. The issue is only present when using Siri or making a phone call, never when playing music - and seemingly only when actually driving the car -- if the car is parked, or NOT moving but still in Drive/Reverse (like at a red light) this is NOT an issue at all and Siri/phone calls are perfectly normal. As soon as I start moving again, issue reappears.
I turned off the Leaf's Wifi, Bluetooth, and "vehicle transmission" for Nissan Connect, none of those fixed the issue unfortunately
I tested multiple iPhones and all have the same issue, all running iOS 15. I tested a USB-C to lightning as well as USB-A to lightning cable, as well as different length cables, and manufacturers for each type (Apple and AmazonBasics) -- no change at all.
The fact that the issue occurs only when moving makes me think there is some sort of interference/signal being sent through the cable or
speakers, which only becomes apparent in "phone" or "assistant (Siri) modes, since they use different audio channels than music, or so it
seems. Quite frustrating for a brand new car, and sad to hear it's been happening to so many for so long!
Unclear who to contact regarding this, Nissan or Apple. It does seem to be specific to the Leaf for some reason.