Do you have an alert enabled for availability of that volume? If so, make sure that you have an action configured to create an Orion event. If you do, then you can use the Events tab of the website to filter events for that node and alert's triggered and see when the volume went down. If you don't have something like this set up, you will, at the least, want to configure an alert trigger with an action to create an event that covers 'all volumes'. This will give you more data to review since Orion does not track availability of volumes or interfaces - only nodes.
You shouldn't have to sift through the events one by one. Why not select the IP Address in question and then select to show only volume events.