high frequency intermittent noise

I have a noise issue that is intermittent. Here is what the noise sounds like:

https://clyp.it/4b233bmm

Here is what I know so far:

The sound affects all components and is compounded if all components are turned on. I have turned off my preamp, phono preamp, leaving just my mono blocks on, and the noise still appears.
I have turned off everything and unplugged everything in the house including my dimmer switch, and the noise still appears.
I have a pair of pro-audio monitors, self powered with class AB amps, and when I plug those into the same outlet, I hear the same noise coming through the pro-audio monitor. So this rules out my big system.
The noise is primarily during the day and goes into the evenings, weekends too, early mornings it does not appear.
I live in a pre-war mid-rise building. I have no ground, I'm using a Nordost QKore grounding system. This did reduce the noise floor quite a bit, but has no affect on this intermittent noise.
I have a cell phone tower directly across the street from my building in Manhattan.
Looking at a real time analyzer, I see peak at 2kHz when the noise appears.

james196911-12-2017 2:30am

james1969 OP Details Discussions Posts This discussion Message User 345 posts 11-20-2017 at 08:52pm Copy Comment URL Report Comment Edit Delete Ferrites are on order. I still need more aluminum foil. 👍🏻
dlcockrum Details Discussions Posts This discussion Message User 2,105 posts 11-21-2017 at 02:06am Copy Comment URL Report Comment Edit Delete Have you thought of wrapping cords and cables with this: https://www.ebay.com/itm/EMF-RFID-RF-Shielding-Copper-Fabric-Roll-44-x-1-of-Material/131893330384?ss... Using this conductive tape to seal the seams and to ground the fabric to electrical ground: https://www.ebay.com/itm/Copper-Foil-Tape-1-5-X-10ft-EMI-Conductive-Adhesive-Ship-from-USA/162095634... Dave
james1969 OP Details Discussions Posts This discussion Message User 345 posts 11-22-2017 at 12:40am Copy Comment URL Report Comment Edit Delete Aluminum foil had no affect on the power cord and the speaker cable with the shorting plug in the amp.
Post removed Nov 22, 2017
kosst_amojan Details Discussions Posts This discussion Message User 2,095 posts 11-22-2017 at 10:52am Copy Comment URL Report Comment Edit Delete I'm not sure where this 700-800 MHz figure came from, but LTE bands usually operate up in the 1.7 - 2.4 GHz region. @atmasphere Nelson is good indeed. Maybe I shouldn't be surprised the F5 is resistant to that kind of interference. It's all resistors and it's designed to shrug off MHz range ringing because of it's crazy wide bandwidth.