SSRS - IE slow first response with FQDN but fast with IP address. Chrome/FF are fast

I see others having this problem but having seen any solution. Problem: 1. On a new IE browser session, the first access to SSRS is fast when the IP address is supplied in the URL 2. On a new IE browser session, the first access to SSRS is *SLOW* when the full server name is supplied in the URL, then fast from then on. 2. Chrome and FF are always fast regardless of the URL. What settings need to be changed to make IE fast on first. Note this is not the sleeping SSRS instance problem. SSRS is up and serving reports without any issues.