Blank bar on the Spectrogram

[KyuubiYoru]

What is the cause of the blank bar on the right side?
I not sure how i can fix that.

[KyuubiYoru]

I changed the audio settings for signal normalization and now it looks like this.

[p0p4k]

Blank bar is the padding.
When training, the model finds out the longest audio length and pads all other audio spectrograms to make all of them the same length. There is nothing wrong in here.