I'm sure this phenomenon has a name, but I don't know it. Another aspect is that I can read English (focusing on that) and listen to Finnish at the same time, and I'll remember both what I heard and what I read. Doesn't work the other way around, or if both are the same language.
For me it's just the latter; vocals don't distract me as long as the song is something I've listened to 20+ times before.
Curiously, I need to match the music to my mood, not the other way around! Any disconnect between how I feel and what is playing gets me distracted very quickly. So some times, I'll be listening to calm ambient, other times I'll be blasting power metal (or even playing some nightcore from youtube). But it's always the mood that sets the music, not the other way around.