Within the NET gateways there is a current bug which affects SNMP triggers for error/crash reporting.
If your gateway is running version 2.1.x version the console wont allow you to delete or amend the default entry within the SNMP portal. OR is some cases I’ve have seen it allow you to amend it but then not actually work as expected. The workaround to this is to simply leave the default entry in the portal and just add another entry detailing your requirements.
At the time of writing NET are aware of this minor bug, and when 2.2.x is released in a month or so’s time this will be resolved. Using the link below keep an eye on the NET/Sonos site for the release of 2.2