Any way to remove NULL/npch errors from syslog?

I am getting flooded with NULL/npch messages into the syslog, making it difficult to make out more more useful messages. I read here that this error comes from a number of sources some of which are closed source. As these messages can't be removed is there some way I could configure the syslog to suppress the logging of these messages? For what it's worth, I am running Merlin 378.56_beta2 on a RT-AC68U. The messages look like so:

Dec 14 16:41:15 kernel: [truncated] L/npch ==NULL/npch...

Any way to remove NULL/npch errors from syslog?