Micromax Q5 has a weird audio set up. I am not sure about other models from Micromax, but Q5 does have a pretty complicated audio refresh system.
The issue happens when you format your memory card on Q5 or when you delete the 'My Music' folder on your memory card.
Micromax Q5 requires a folder named 'My Music' on your memory card. All music files should then be transferred to 'My Music' folder. Once you transfer all music files to the 'My Music' folder, you will be able to see all the songs in your audio player. If you can't see the songs, just refresh the list.
It is important to create a new folder named 'My Music' after formatting the memory card. Otherwise you won't be able to play the music files from the audio player.