EDIT: I have a computer with Teamviewer on all locations... That is the only thing I can think of connecting them...
I have a bunch of scrypt miners that all have teamviewer installed but none of them have been diverted.
Would be interesting to know if on client-side anybody is mining nxt or using "BTsync Remote Storage".
Never mined nxt but I have BTsync installed on one box that mines scrypt on multipool. Not sure why you would suspect BTsync of being involved though.
As far as I can tell none of my miners (scrypt or sha256) have ever been diverted. Most of them are on the same network which uses a static IP through a business class ISP. The one with BTsync is on a home DSL.