My mother had me look this phone number up also.  She got a call this morning, same thing happened.  Asked for my dad and when my mom said he wasn't there, they disconnected and my mom said it sounded like a fax machine number.

I believe what people are reporting as a fax machine noise is actually a computer modem as this number shows up as a dial-up number for an ISP.
I've also been receiving calls from this number and I blocked it the first time it showed up and have never answered it.

caller asks for my husband.  When I ask who is calling they answer Farm Supply.  He is responding to a request for weed and brush removal.  We have no need, as we live in the burbs.

Called - left no message

970-252-4197 Keeps calling.  I won't answer.