High pitched tone in all rx_fm output (maybe PL tone?)

[Brandon4466]

Hello! I am able to successfully get FM raw audio from rx_fm using my HackRF and convert it into a wav using sox. However, all audio comes with a very high pitched tone with it, I'm thinking it's a PL tone.. This tone isn't present in any other SDR software that I have used so I am assuming that other applications must be applying some sort of low-pass filter to get rid of this tone. I have attached an audio file with the tone below to show what I mean.

Do you know how I can get rid of this tone? Maybe using sox?

I would be very appreciative for any help! Thank you! output55.zip