WAN Smoothing Ping Timeout

I have a customer who has multiple sites and running ERP Software which is very sensitive to Packet Loss. I have installed for them Peplink with SpeedFusion/WAN smoothing as a Proof-Of-Concept. The customer is monitoring the connection continuously, and they are happy about the performance, except that they notice infrequent ping request timeout. I have checked the Event Log, and I could not find any WAN Disconnect event. Also, I have noticed that when we ping two different IP addresses across the SF Tunnel (with WAN Smoothing enabled), sometimes the PING Request Timeout will be experienced with one of the IP addresses, but not with the other IP address at that specific moment of time. My question: What can cause this request timeout? and what configuration we can experiment with changing to eliminate this ping request timeout?
Note: PoC is between Head Office and Branch office. Each of the offices has 2x WAN connections.

I have seen this before FW 8.0.1 what version are you using?

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Running “8.0.1 build 4368” on both ends

I have a technical question for me to understand better the WAN Smoothing Aspect of the SF VPN: If I understand it correctly: When the Transmitting Balancer Unit wants to send a packet, it will replicate it over the available WAN connections, then on the other end of the SF Tunnel, the Receiving Balancer will take the “First” arriving packet, and will discard the remaining “Redundant” packets. Now the question: How does the sending Balancer “Tag” the redundant packets to inform the receiving Balancer about the relation between these packets and that they are redundant? Does it add its own custom “Tag” to all redundant packets (or maybe use the SF VPN header fields)? Or does it rely on the Tunneled protocol headers (such as TCP sequence numbers)?
If it relies on the Tunneled protocol header, then how does it handle ICMP Ping packets (which to my knowledge lack that numbering fields)?

This is not related to the original protocol. WAN Smoothing is a feature of SpeedFusion, which is a VPN protocol that encapsulate packets with extra header. There is an ID for each encapsulated packet, so we can identify duplicated packets, either generated by WAN Smoothing or other networking devices in between, and we will discard the redundant packets on the receiver side.