Quick post to put aside some of the myths relating to encoding.
First: Enabling the encoding setting only takes effect if the file is not MP3. If a file is already MP3, it will not be encoded again. The reason:
Setting a higher bitrate in the encoding settings does not increase the quality of files saved.
Look at it this way: You write a description in 60 words of an object. You delete a sentence or two, then hand off the paper to another guy, who knows nothing about the object. You tell him to put the removed bits back…. It can’t be done, with just the paper.
Another analogy: Imagine the encoding process as using a cookie cutter on dough. You can’t bring back the dough that was previously cut away by using more cookie cutters (re-encoding) on the dough. It’s simply not possible. You can only remove dough(data), not add it back.
What’s more, by encoding additional times using the same algorithm, quality would be further worsened even if the bitrate is the same because it’s using the same method to determine what data to remove. To borrow the dough analogy again, if you use the same cookie cutter on cut dough, it’s not possible to get it perfectly aligned each time and so you remove more dough with each successive cut.
Hopefully that explains why you don’t magically get 192kbs files even though that’s what you have in settings.