blob and buffer errors

I am using the latest KNIME version on the Mac (latest OSX) and keep getting errors on nodes such as these below which stops the node from completing. Any ideas what the problem is;

ERROR X-Aggregator 0:204:1 Execute failed: Error while writing to buffer, failed to write to file “knimecontainer20200810_8568262710548603014.bin.snappy”

and…

ERROR X-Aggregator 0:193:1 Execute failed: Error while writing to buffer: Blob file location “/Applications/KNIME 4.2.0.app/Contents/MacOS/col_1/000/000” does not exist

and…

Execute failed: Error while writing to buffer, failed to write to file “knimecontainer20200810_7894528850755034336.bin.snappy”: /private/var/folders/dx/lggccpg…

Any ideas. I have it happen on other nodes too.

Simon.