Hell no! I listen to music all the time when writing poetry.
And yes, most of my music is instrumental or industrial/techno, and the most inspirational pieces are without words.
We write poetry in order to express something in ~words~ and this includes music.
By your logic (in this statement), looking out at a landscape and writing a poem would be plagarizing the landscape.
Music induces emotions. Call that a "subconscious message" if you will, my friend, but the truth is that a lot of, if not most poetry is written with the influence of outside forces. It's called inspiration, not plagarism.
Poetry is the talent of putting something to words. If this is music, landscape, emotions, or anything else, it is not plagarism.
Plagarism is, in my mind, the writing of something that was already written.
Sometimes I feel like I am plagarizing my imagination when I write about dreams.
Of course, this is just another topic that I won't bring up.
Well there you have it, my answer.
Oh and if you ever want to try writing a Rengay or something to the same piece of music, just let me know on ICQ. I'd like that.
Stupidity makes the world go around...and people like us laugh. ~~Elizabeth, to Allan