Is there a way to suppress NUnit errors and failures displayed on console output?
I tried using the command line options: /xml, /out, /err. But still I get the output in the console.
From your use of the /xml option, I can see you are using an older version of NUnit, however, the answer is the same for newer ones as well.
There is no way to change the report output produced by the console runner. You can redirect the entire thing to a file, or even to the null device, but you can't suppress parts of it.