Wouldn't hurt to try a larger size. At my fitting, the guy measured me for a 36cm, which felt extremely narrow, and left me with neck pain. I bumped it up to a 38cm, in the short and shallow (salsa), and still had problems. I thought for sure I must be a 40cm, so i tried a larger bar, by a different maker (Ritchey). Definitely felt too wide. I even tried a different shop, and he said I was a 38cm for sure.

I had posted my dilemma on the boards here, and someone actually had an extra pair of 38cm, and offered to send them to me. They have been nothing but awesome, no problems at all! They are Bontrager Race bars.

So, it could be that you need a different brand, or maybe go up a size. I found that the Bontrager 38cm I have now have a lot more room across the tops, even though I primarily ride in the hoods. It's nice to have options though! My other 38cm (short and shallow), there wasn't enough space for me to rest comfortably.