nothing out of the ordinary as a treat or for dinner? Chum gets this pretty often and I followed the advice from this forum by giving him a tablespoon of pure pumpkin with his next feeding and it literally got better by the next time he had to go.
I am on the pumpkin band wagon as well. If it is soft serve and sounds like it just started try the pumpkin trick If it doesn't improve then maybe call the vet.