SNAT pool is configured but source translation is set to None on Virtual Server and there is a pool attached to it which has Allow SNAT as yes? Does translation happens in this case when client sends a request to server? As per my understanding it shouldn’t but I’m seeing source ip from snat pool list for server side connection.
Allow SNAT at pool level option specifies whether the pool can load balance secure network address translation (SNAT) connections. The default value is yes. If there is no snat confiured at VIP level then original client IP would be used across server side connections. Please check if there is any iRule attached to the VIP as SNAT can be also achieved using iRule.