Altering music files question

I have been trying to 'upconvert' my lower quality sound files to high quality Mp3 Flac and WMA. When I do so I get a popping sound at beginning of each song. Would this be due to program limitations or could it be the converter i'm using?
Can a (for example) 192kbps mp3 truly be upgraded to a much higher quality?
I'm new to this digital format and compression of songs.
Any helpful response would be much appreciated.

 

What did you use for converting?

 

You can convert them to a higher bitrate but they WILL NOT be higher quality. In most cases, they will sound worse as your 'popping' problem shows. It matters not what converter you use.

 

Thanks.

 

Just Playin is absolutely correct, you have to look at the lowest denominator ... in this situation lower quality music, its the same as having a set of RCA cable running from your satellite box to your TV and an Optical cable running from your TV to your Amplifier, it wont be Optical quality it will be RCA quality