Logic pro X: Very weird Bouncing problem!!

Hello,

Ive never had bouncing problems since yesterday. My song lasts 5:40 and I dont know why, since the last export, from minute 4:34 till the end it starts to sound only in the right side of my headphones and speakers and on the left side, can be heard a tiny crackling sound.

Im not sure if this is the cause of my issue but minutes before bouncing, I was mixing the song using a Fiio Headphone amp and when I decided that everything was alright, I bounced it, but somehow during the process, I mistakenly disconnected the usb headphone amp.

Though the song was exported, I noticed that at the end there was no sound. So I connected the amp again and tried for a second time and the song only sounds at the right side from minute 4:34.

The strange thing is that the song sounds correctly in my Logic session, it just happens in the bouncing process.

Ive tried to change buffer sizes, checked sample rate, bit depth, bounce with my mac's audio device, etc.. And nothing.

What could it be and how could I fix it? Hope someone can help me, Ive been working in this song so much...

Thanks in advance.