I have the weirdest phenomenon: every time I want to make a cut in my video, using blade, the audio fades out where I made the cut and then fades in again. I have been searching everywhere I can, but find no solution. Why is it doing this? How can I prevent this? I want to edit my video without the audio getting all messed up with unwanted fades. Please help if you can.

As pointed out in your FCP.co post, it is a mystery. Until one of us can replicate this, there's simply no answer. I would recommend filling out the FCPX feedback form found in the Final Cut Pro menu.

How about more information. I cant see why you need to use your blade tool to make cut and then fade out. That is how i'm reading your post.

The fade seems to be made automatically when he makes a cut with the blade. Personally, I believe you need to learn the proper edit trim tools. The blade should very rarely be used for anything when you learn the edit trim tools properly.