Tp-link, Care to reply here?

  @patrocle Hello. Did you get a reply? I have the same question. How do I mute the camera's voice for intermittent wifi connection? It is quite disruptive especially at night. I don't know if the new updates within the last two months are causing this issue. Thank you for asking this question.

  @sfoto Nope never got any reply back. Looks that no one is listing around TP-Link team, but i will send a link directly to support soon you can do the same and let me know the outcome

  @sfoto 

found this here:

Hi,
On the Tapo app > camera's Live View page, please tap the Call icon to go to the Voice Call page, then tap the icon at the top right corner of the Voice Call page, try to reduce the speaker volume, and check if it helps.
Best Regards

https://community.tp-link.com/en/home/forum/topic/811538

Will have to try it

  @patrocle 

Thank you very much! There is also an option to completely turn off the speaker (like pressing a mute button) by pressing the "Speaker is On" icon at the lower right per your screen shot. It should then read "Speaker is Off" with an "x" next to the speaker. I guess one could toggle this setting back and forth to turn it off and on in addition to lowering the volume like you suggested. I currently do not use my cameras to relay my voice over the C120, but it is a good feature to have. Therefore, I will keep my speakers on off or mute on all of my cameras. I greatly appreciate your help and will update if this does not work. Lately, I don't know if there were software updates, but fortunately, the voice notification has lessen significantly. Thanks again!

  @patrocle 

Update. I think the method you mentioned to minimize the volume is the best. The "Speaker is On" might only be used for the phone itself whether to speak directly to the mic on the phone or via speaker. Your method can completely lower/minimize the "Camera's Speaker" directly on the C120. Thank you again! :)