Hot cross buns cross mix

Heya bakers I'm looking for some advice  working and knowledge working with cross mix.

I've been having a issue with my buns splitting due to the cross mix. I don't know if anyone has had this issue and I don't have any pictures at the moment to post to refer to I just hope you all know what I'm talking about.

I just want to know if other bakers have/had this issue and if so why is this happening and what I can do so my hot cross buns look perfect when taking them out of the oven?

Thanks for your time