We recently updated our Grin29 miner. Since NBMiner has not been updated by the developer after the fork we had to replace it with a different one, called GMiner.
If you are mining Grin29 (now called Cuckaroom29) please make sure you updated BetterHash to version 3.139 or higher and also go to Settings / General and click on "Re-download all miners". After the miners are updated you should see "miners pack 6" or higher displayed on the bottom of this page.
The update is a manual one, so we kindly ask you to re-download all miners in order to benefit from the update.