NUnit 3 - Only ever one agent

Hi,

I've got a problem using the teamcity nunit runner type. I've got about 20 test dlls but only ever one nunit agent is created to run them, meaning they're not being run in parallel. I'm not talking here about the new parallel nunit 3 functionality, but per assembly parallelization.

There's no problem when I run nunit from the command line (lots of agents are created) so I know it's not a problem with nunit itself.

I'm using Nunit 3.4.1 and teamcity 2017.1 (build 46533).

I've tried forcing the 'workers' and 'process' (setting it to multiple) command line args but they don't help.

Thanks,

Tom