Chosen Solution

Problem with an iPhone 6 During calls from this phone it can be very hard to hear you on another line Whatsapp calls and voice memos tell me the mic is working perfect but for cellular calls it seems to be poor Any ideas?

I’m wondering if it has to do with your cellular connection, and the Lightning dock is the culprit. Try the force restart first, if that doesn’t take, I would guess it has something to do with either the cable on the Lightning dock, or one of the chips on the board. The 6 and 6+ are notorious for having issues with the chips becoming unstable due to the weak frame iPhone 6 Lightning Connector Assembly Replacement iPhone 6 Lightning Connector and Headphone Jack

Hi, I have not heard this before but I would try the following right off before going any further. Try a restart. Hold POWER and HOME at same time until Apple logo appears and then let keys go. Try it and see if that helped. Restore the phone. backup the phone in iTunes or your favorite backup program and the do a hard reset. this will force a reinstall of the firmware and then you can restore from the backup. Hopefully one of them will resolve that. If not, it may be a hardware issue that needs further testing. Mike