My ISP called me today.....?

[Brandon]

Hello and thanks for reading.

I received a call this morning from my ISP, saying that they "were doing network maintenance today and noticed that my modem is consistently maxed out throughout whatever time period(s) they were checking". He further informed me that "if it were to continue I would have to find my service from someone else". He also mentioned some previous abuse report, which I remember nothing about so I am not sure what that was. Could that mean they flagged me for traffic before?

He asked for me to call him back to find out if I know what may be going on, which means I'm sure he considers me a pirate or something lol.

I am a 5 person household, with extra friends or extra family members at the house frequently. Everyone whom I trust has the password for my router on their phones and tablet and laptops. That being said, there are multiple devices constantly accessing the internet: Netflix is run almost all day, every day, on my desktop connected to the tv in the living room and/or my children's Nabi tablet. My wife and I download torrents and I purposely set up queues and speed limits to make sure it's not taking away from the other devices (I pay for 10mb down and 1mb up, so I set the speeds considerably low enough--usually around 500kbps). I always make sure to shut off the client after use so it is not sucking bandwidth. I also game online very frequently.
I pay for unlimited service so I don't really know how to take this. How can I avoid my service being shut down and still do the things I enjoy with my service? Could this have been caused simply because they noticed bittorrenting traffic? Or would it be because we reached some sort of soft cap set by the provider?

What should I say when I call him back? I don't like the idea that I'm being scrutinized and threatened with service shut down because I am using what I pay for. I just want to make sure I am not going to be disconnected because there are no other ISP's where I am and I feel like these guys are taking advantage of that.
And this is a legitimate call from one of the managers. It isn't someone running a scam.