Lost connections

Hi, we are running XIr2 over Citrix. After a certain period of time (a few minutes) of leaving a deski session, if I return to it, and attempt to refresh the data, or access the universe in any way, it appears as though I have lost connection to the universe.

I am presented with errors like "Connection or SQL sentence error: (DA0005); Exception: CS, Unexpected behaviour", and "A connection required to refresh this document is unavailable (DA0004)".

Thanks.