what greg said here - the LS100 manual states that xlr is wired "single ended" which essentially means there is no ground.
I suppose its possible that your speakers are wired in reverse, but I’m almost 100% certain that 2 hot would be standard positive in singled ended config.
I suppose its possible that your speakers are wired in reverse, but I’m almost 100% certain that 2 hot would be standard positive in singled ended config.