I'm not familiar with it, but do you remember what might have changed around that time (Did you upgrade NVDA, DocuScanPlus, Windows, etc)?  The Docuscan website mentions a new version 3.  It might be worth either trying the release candidate of this version, or alternatively going back to the previous version to see if that makes a difference (IF v2 works but v3 doesn't, it would definitely be worth letting Serotek know).  They also have versions for if you are using System access or if you are using another screenreader such as NVDA, so you might need to use that second one with NVDA.