Seeing close to 100% SSL connection error rate one of the monitored servers. The majority of errors are "Invalid SSL Content". Client Segments Missing Rate and Server Segments Missing are very low so this does not appear to be a case of missing segments in the feed.
Customer has Citrix Netscaler Load Balancer in their environment which is sending health check traffic across the monitored network. This traffic uses no handshake which FxM sees as Invalid Content.
Disable the Health Check feature on Citrix Netscaler.