Yeah I don’t have WiFi calling enabled. The voice connection will be clear for a little bit during the call then get choppy where words get cut out etc. It has happened on multiple calls in multiple locations today. I guess I will call Sprint who will probably just send me to Apple
In which case, I feel for you. Audio quality is so very important to what I need an iPhone for. Probably you too. Unacceptable for a device costing north of $1k. The only other advice I have is, wired headset plugged into the lightning port; that also does wonders for audio quality. Even with Bluetooth gear improvements, wired is the way to go for the best audio.
But if you are on cellular only, and you still have choppy cellular call audio, then this is the worst possible situation. It shouldn't matter what your peripheral gear is, cellular/LTE-only voice should be clear with no chop, no drops. If it continues, I'd return it.
Still rocking my sim-free iPhone 7 with the Qualcomm radios (model MN8G2LL/A), carrier Verizon, cellular audio is top-notch, especially with wired headset. About as close as you can get to landline quality when using a cellphone.