I fix it by lifting heavier.
My delts BLOW UP something freakish. However - I like that because I still look slim even when bulking ... LOL.
But ... by "upping" the weight - my delts are forced to nicely ask my pecs to get off their ass and help heft the weight.
So now - I only lift heavy on chest and for only 4-5 reps per set.
I used to do an alternate "heavy" / "light" days workout where I did heavy chest on Mon and light on Thurs. I wasn't seeing results so I went to heavy all the way around and I'm pretty happy with the results.