Slow throughput using Google Cloud Storage

Started using the Google Cloud Storage connector about a month ago to duplicate my local backups.  I am running BackupExec 15 (ver 14.2) on a Windows SBS 2011 Standard server.

When duplicating the Exchange files and the Active Directory files, I notice the throughput is very slow - typically around 50mb/min, but duplicating files is at speeds I would expect on our internet connection.

I've disabled anti-virus and email scanning on these files, but that hasn't helped.  Wondering if anyone else has experienced this or has any guidance on configuration.

Thanks.