IPSec Slow - Fixed It and Then Slow Again After Reboot

[dcline]

I have a common issue where IPSec is just slow, getting around 1 - 2 MB/s between (2) OPNsense VMs as a VPS.
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I messed around with various MTU/MSS settings and that didn't help, I eventually turned of Interface Scrubbing on both OPNsense VMs and BOOM 15MB/s.

I then rebooted them to make sure it wasn't going to stick and....nope...back to 1 - 2 MB/s.