So I just got it in today, I hooked up the effects loop with George L cable and it worked fine, I used my tweed rapco cable as the intrument cable and it worked fine, and when I went to hook up my monster bass cable as the main out, it wouldn't fit. I tried switching it with the tweed cable and it wouldn't fit in the front as the instrument cable. Simply put the monster cable will not fit in any of the 1/4" jacks on the whole unit. What's the deal? I have never had this problem with any of my other gear, and I've never heard of this problem either.