I am on the latest beta, but I have seen this behavior often enough in earlier releases.
I use Windows RDP to remotely access and monitor SGP.
I lost wireless connectivity for a few seconds and when I went back into SGP, the current running event had changed from 20 seconds to 20 minutes.
This is not the first time that seconds have changed to minutes on 1 or more events seemingly randomly.
I notice that the exposure edit box/dropdown has the focus when this happens.