A Nothing Phone 2a is being used on my daughter’s side for WhatsApp calls with me. The microphone fidelity seems low but suitably sensitive to adults. The connection is usually fine, the video is fine, and my voice comes through to her fine. My 4-year-old daughter’s voice fails to come through about most of the time, however. I initially suspected it was a WhatsApp problem, but the problem persisted with three different video call platforms. Then it occurred to me that some fancy audio processor might be construing a 4 year old excitedly parroting something from the story we’re reading as background noise. So, checking here 
WhatsApp Video Call - Low Audio Quality
PrabhashJain When doing such video calls, are both your device and the recipient’s device over Wi-Fi? Sometimes I find at least, audio quality is impacted by the signal. Since you have also tried multiple video platforms and experience the same problem across all of them, it might be worth reaching out to support.
Louis ☕️ changed the title to WhatsApp Video Call - Low Audio Quality .
I have the same problem
4 days later
I also have the same problem. I am unable to hear sound of my 4 year old nephew although the sound of adults beside them is very clear.
7 days later
PrabhashJain same problem here
I would suggest all the users who are facing this problem to reach out to Nothing support, could be of help on this issue
6 months later
@PrabhashJain was this resolved by reaching out to support? What was the resolution?
4 months later
PrabhashJain it’s resolved?