ReadyNAS 6.7.1 failed and slow copies of large file sets

My system was updated to ReadyNAS 6.7.1 today.   Ever since the upgrade, copying files to the ReadyNAS are slow and often fail.   Small file sets are fine < 1GB although copies tend to slow down dramatically in the last 30%.

I was having issues on one PC copying file sets that were greater than 2GB.   It would either pause for long periods of time or fail with "connection issue".   I attempted a large copy from a different PC on the same network and it never succeeded.  It always seemd to fail on the last 5%.   It was similar to what I saw on the other PC. 

I'm currently using Windows 10 on both systems.   Prior to the upgrade it was fast and never failed. 

Any suggestions?