After answering a call with the handset or with the desktop app, I get a repetitive series of beeps during the entire call. Anything I can do to stop that?
If this happens on Windows and you have a USB headset. Try going to Zoiper -> Settings -> Audio, there you will see a few "HID" options(Jabra, Plantronics, Generic and etc.). Disable all of them. Restart Zoiper and see if the issue would reappear.
Tsetso's advice worked, though now the headphones don't beep when I get the incoming call. It would be nice if they beeped when a call was ringing in, and then stopped beeping when I answered. As it is, I get no audio notification of an incoming call, or I get beeping all through the call (which the caller can also hear, though not as loud).
(I'm using Plantronics Savi 7xx)