I found this sentence in a song.
Is it correct?
It's always raining since you been away.
I think it should be this way:
It has been raining always since you are away.
Are both the same?
This is lyrical writting and not correct English
The term "since you been away." and "since you been gone" are commonly used in songs and are originally American slang.
Your sentence "It has been raining always since you are away". is not very correct.
This would be better "It always rains, since you went away"