If you looked at the thread directly beneath this one someone asked the exact same question! :)
Firstly, it looks like you are doing a little too much there. Remember bis take quite a beating training back so they are more than warmed up already. I'd knock at least one if not 2 of those exercises off your routine.
Try a varied rep range aswell - bis are a small muscle so don't use a massive weight, do lighter try upping the reps and really feeling the contraction.
Another idea might be to train bis with chest and tris with back so in a way you'll be hitting bis twice a week (one of the times being indirectly through your back work) which means they will be fresh when you train them on their own as they aren't really used during chest!
Soreness isn't everything - check this thread for other possibilities:
Whats best?