Hey Carlos,
thanks for the file!
From what I can see, FTF is right: This file is NOT a true 48kHz/24 bit file.
A true 48 kHz file should show a clean specrum up to 24 kHz.
But as you can see in the spectrum, there is a clear cutoff at 22 kHz
This is a strong indicator that the source was a regular 44.1 kHz CD rip.
This does NOT mean, that it is bad quality - the cutoff frequency of 22 kHz is a good indicator that it is a high quality file. But to be honest, it looks like a fake: It claims to has a samplerate of 48kHz but it is only 44.1 KHz.
Please refer to the user guide available at
https://fakinthefunk.net/userguideSince the file still is good, you might want to accept this: That's why there is the option "allow cutoffs above ... Hz" in the settings dilaog. From my point of view, files >= 19800 Hz are good.
CU
Ulrich