I recently purchased a Sonos Connect. Previously I had used an Apple Airport Extreme to stream music from my macbook pro to my audio system. When I went to plug in the TOSlink, it was "too small" for the input plug. I could almost turn the TOSlink connector around in the slot.
All 3 TOSlink cables I have have 2 "bumps" opposite one another. I have attached a picture with arrows pointing to the bumps, thinking it might help.

The digital input on the Connect looks more like what some on the interweb have described as being D-shaped.

What am I missing here? In other words, why won't my TOSlink cables work in the Sonos Coneect?
Thank!!