Hi Jason
Have you checked ?the logs? From SSA and mostly form Spectrum (wrapper.log)?
We had encountered this type of error in the past (but not anymore) when we were doing spatial calculations on heavy and very precise geographic tables with Spectrum, but not with SSA.
And often, it was a server memory problem. So , since we have increases the RAM of the server, and the memory allocated to Spectrum Spatial.
Another point (which applies to all GIS), warning to the projection system of the different maps / tables. To avoid any problems of performance, we use wgs84 for the tables. This avoids recalculations of coordinates (still very resourceful).
Especially if you have tables stored in spatial databases (oracle, potsgis, etc ...).
Best regards.
David