Wireless Router - Noise Culprit

I recently migrated all my gear onto a new Symposium rack (which I love btw). In doing so I also moved my router and cable modem into close proximity of the rack (it used to be about 8 feet from the rest of my gear).  I quickly noticed a really obnoxious "motorboating" noise when using my phono stage if volume was turned up high but stylus not cued yet on the record. Initially I had no idea what was causing the pulsing sound and I feared it was a power supply, tube, or electronics issue in my amp or preamp.  By dumb luck while checking connections I incidentally moved the ethernet cable and noticed the pulsing fade and come back depending on how I moved it.  I moved the router and cable modem back about 8 feet away from the rack and the problem has completely resolved.

This makes me think about the kind of digital/electrical noise we may be unwittingly introducing into our systems.  Anyone else noticing problems like this?  I really thought I had a major issue on my hands and was relieved how simple the fix was.