GRAction

Just got my Promedia 2.1 THX (not bluetooth). I hooked it up and tested in Windows 10 and the left and right channels are reversed. I checked the speaker connection at the sub multiple times and it is definitely correct. My old speakers worked fine. All I can think is that the audio cord wit the miniplug was wired backwards? I can switch the speakers at the sub but I'm afraid headphone jack might also be reversed. Has anyone else had this problem? I saw one other person on the massdrop website with it.