Need help on where to start

I drive a 2007 standard v6 Tacoma and its been my daily driver for the past 4 years getting up to 190,000 miles. Recently I've noticed a horrific waffling/knocking noise from what sounds like its coming from the transmission in every gear until 5th. It starts low in second gear and only gets louder until its extremely noisy in fourth. I had a friend take a swing at it and tell me that it could be a pressure plate in the clutch. I was hoping someone could point me in the right place to get started before I waste money running around to shops looking for the someone to do a diagnostic without ripping me off. I also tried to post an audio clip of the noise to narrow it down but unfortunately could not figure it out. Any help would be much appreciated, thank you!

 

Could be a cat converter breaking up inside. But I think that would make noise even when not moving.

 

When your rolling along in 4th and press the clutch in to coast does the noise change?

 

I only seem to hear the noise when I accelerate. I've tried engaging and disengaging the clutch and its comes back after I let off the clutch and press the gas again. Thank you!

 

Time to go fishing?
1) Is the noise speed sensitive? ie:when you hold a gear and speed up or slow down does the noise change with the speed.
2) Does it make noise when driving if you rest your foot on the clutch pedal?
3) Does it make noise in rev?
4) does it make noise if you rev the motor in neutral with your foot not on clutch?

This to start

 

Could be a bad u-joint, that makes noise only when under torque.