Not heard that one but I had At The Mountains Of Madness books. I'll read all sorts and have a fair bit of patience when it comes to reading*, can usually get through a lot of pages to get to the nugget of decent plot but the one I read got launched across the room cos it was just crap. Gave both books away to the girl who lived downstairs if I remember right.
It was all a bit Unseen, unheard, unimaginable shapeless cosmic horrors slithering about in blackness.
Years later I got a download of the audio book and it was just as bad.
Quite possible that Shadow Over Innsmouth is better, I've never read it.
*Got through 1340 pages of pure anticlimax that was called Shogun, I'd call that pretty determined anyway.