Deny: policy violation... sometimes...

Running Fortigate on 6.2.3 and I have a policy set to basically allow all traffic and *sometimes* I get Deny: Policy Violation in the logs referencing this policy.  What could be causing the deny?  It does not happen all the time, just sometimes.  Traffic is hitting the policy correctly.

config firewall security-policy   

edit 35       

set uuid <redacted>        

set name "Outbound Allow Everything Else"       

set srcintf "Trust"       

set dstintf "virtual-wan-link"       

set srcaddr4 "all"       

set dstaddr4 "all"       

set enforce-default-app-port disable       

set service "ALL"       

set action accept       

set schedule "always"       

set logtraffic all   

next

end