Default Media Problem

I am having a minor problem in my recently bought Asus Zenfone 4

The problem is that both the asus music player and google play music app are showing only one same album art for every song, allthough each song has its own album art and also when i play those songs on pc then the respective album art appears.

I organize my song collection by removing all other tabs except the title and album, the software i use for this task is Mp3tag.

so can anyone please point out the solution for this problem.

also i wanted to ask if the beta app of vlc is safe to use on my device.