Local Interference on 4626kHz

Reception of the UVB-76 signal on 4625kHz has been disturbed for last two weeks or so by an unknown noise source. I have had no luck figuring out what it is so far, but it does look like a network-over-powerline thing someone could be using at the neighborhood. 

Judging from 24-hour waterfall pictures it has no relation to shortwave propagation effects (i.e. has to be relatively local) and does not change in frequency nor time, so it cant be from street lighting, phone charger gone grazy, plasma TV etc. It is also apparent with other radios I have, so it is also not the equipment at the streamer.

The noise stripe is repeating itself after every 50kHz from 2MHz to around 6MHz effectively rendering my shortwave capabilities to nil and does not seem to have plans for going away, so I'll have to start searching for the source!