You can easily check the software version with a TZT or TZT2.
For the NN3D, you can run the update program and it will show what version it is; if it is old.
If you don't own an MFD it is possible to check and upgrade the sounder via a PC but this is normally done by a dealer because of the risk of creating a toaster. If you wish to assume the risk; I am sure you can get the software by contacting technical support.