If you are having issues with MAC PC's receiving calls, one way audio, etc. Please install the Apple Telephone application online by clicking the link for Mac App Store - Telephone.
NOTE: This is a free application.
To Transfer A Call:
- Click on Call from the menu
- A window will pop up asking for the number you want to dial. Type it in and hit the Call button
- After you connect with the person you dialled and told them who is waiting to be transferred, you can then go ahead and hit the Transfer button to transfer the caller to them