Thanks, Dan. I'll see what I can do.
I run a Tomato-based router, which should be very secure. And for me, the issue started occurring on my iOS device when I was away from my home network. I was gone for a month and only noticed the problem occurring on my Mac when I returned. But I'll check and reset everything I can.
I look forward to hearing the results of your investigation Ron, Sorry I am useless when it comes to this stuff.