Illegal Phone Tapping I Think My Boss Is Tapping My Phone - How Can I Tell?

I think my boss is tapping my phone - how can I tell? - illegal phone tapping

Usually, when I set the phone at work if your work or profession, it sounds like someone who listens to my phone. I worked there for 4 years, but it started a few months. Sounds like you would on a landline, and someone else picks up the phone, how to get a piece of cake, then after a while. Is there anything else I could do this noise? I do not use the phone, because someone at work, but my boss is shocking to me, so I think I could spy on me. I really do not know. Is it possible that I could touch by phone to say? It is illegal eavesdropping in the workplace? Any information would be very grateful:)