How about your Facebook messenger? Viber? Normal phone calls? Also, have you tried checking WhatsApp app permissions? If you’re using headphones you should give WhatsApp permision to find nearby devices.
Whatsapp Call Clarity
Same here…WhatsApp videocall mic problem..have to shout for other person to hear
Yeah camera quality is like 15k phone on video call
Do you face such issues when Wi-Fi is on or off, or both? I’ve always found that WhatsApp call quality isn’t that great on any device I’m using, including camera quality. I think this is more of a WhatsApp problem where they aren’t optimising correctly 
8 days later
Clarity is good in comparison to normal call but sometimes it fails to detect my voice normally in earpiece mode and the other person thinks I’m not even replying which never happened to me before purchasing NP 2 and never faced such issues in other phones like im facing in NP 2
Louis 
could be an optimization problem maybe
DrNaveedKhan exactly that’s the point I too have to make efforts to speak louder otherwise it fails to detect my voice
Louis both
3 months later
I am also facing the same issue. Is there a solution yet?
AkashYadav_XWtaA8YMPz this issue isnt solved it i have this one also…. furthermore in whats app and maybe in snapchat too,the quality of voice message recording is so poor its pathetic quality.this issue is since the beginning…nothing team still havent solved it yet.
10 months later
TejasMaisuriya is it resolved.?