Recently got a WM-F59, plays tapes and radio works fine, but when I play tapes, it has this everpresent hum. It's less prevalent when Dolby NR is off and ramps up when it's switched on. It's present even when fast forwarding and rewinding. I've uploaded a clip of the noise, it's a little more noisy from being recorded but it's pretty similar. Any idea what's causing it and how I could fix it? https://clyp.it/g1gl1fth - HEADPHONE WARNING, REALLY LOUD
