Is my Onkyo Receiver toast?

I have an Onkyo HT-R290 Receiver, which I believe is low end. I know nothing of the internals, only that it works (or used to now).

Today I started by putting on some music, played from my phone through a 3.5mm - 2xRCA cable.

At first I didn't notice the problem, music was playing fine. But after about 20 minutes I had to turn it off. At the higher volumes - anything above 30 - I had a really strange noise coming from the speakers. The song plays fine, but it seems like any sound between 2000-8000 HZ is magnified. This results in a migraine causing noise, as if the volume was at 70 with those levels.

I tried diagnosing the problem myself, and here's what I tried:
- Disabled all equalizer, effects, additional audio options. Basically just the naked sound coming from the audio source.
- Switched to a different source... Streamed the music from my phone to my Chromecast (to eliminate the cable).
- Turned off all ESP, effects, etc from my phone as well.
- Took a 50ft long 3.5mm cable and went directly to my receiver from my PC in another room.

All of this done, I still have that annoying sound. I tried different songs, different artists, games, everything.

I'm not sure if it's the receiver or the speakers themselves, I have no other speakers to test the receiver with unfortunately.

I've added a recording using my phone, I'm unsure if it will be heard properly.

You can hear the noise I hear best when Brandon Boyd is singing, around 30-50 seconds in.

It's not as loud in the audio clip as it is in person.

http://www.filedropper.com/record0001