Fog issue using iam profile and fetching urls from aws

Using Fog w/ AWS instance profiles and after 3 day my s3 urls are no longer working. I'm getting fresh urls, but the error returned from AWS is The provided token has expired. Restarting the application gets everything working again, but no errors other than the one from AWS are present.

I have read that switching to keys should fix my issue, but I was hoping to keep my iam profile. Has anyone run into this?