We always recommend our customers to use a good pair of headsets.
This is because the audio quality will improve making your communications more professional, and the configuration with our apps will be easier.
For this, you just need to make sure that your settings on the app are not on default but on the speakers or headset you are using.
As seen here. The headset is the chosen one instead of the default. If you can try with any headsets that will really help.
(Mac Desktop App)
If you have your settings on default, the audio setting will change according to the system default preferences. Which you need to match with the right headset for both output and input.
Having the desktop Toky app on a different audio configuration than the system can cause the audio not to be captured for the calls.
We also recommend you to refresh the app in case you just unplugged or plugged your USB headsets after you set them up in the right way.
We have more articles about the headset configuration here and look for other articles on our help page.