Solution posted here: Recording quality different from on call quality - #2 by navaismo
I worked till midnight last night with the tech support from OpenVox and we finally found the issue. There is something funny with their Ethernet ports on the new box where port 1 can only see slot 1, to see the others I plugged into port 2, but had left port 1 also plugged in - which effectively gave it 2 routes with the same IP…
That would be why it was recording 50% slower, because in a round robin of receiving it would take a packet from port 1, then port 2, then port 1 again, but only 1 of them would have data. Unplugging one of them resolved all the issues.