This issue is probably due to a wrong cached certificate for audirvana.com.
You need to open the KeyChain application
And then select in its View menu to show the expired certificates.
You can then sort the list by expiration date, and then remove the audirvana.com one that is expired.
Then reboot.
When launching Safari, and browsing audirvana.com there should not be any question regarding the ssl certificate. If any then be sure to have deleted the expired certificate in the operation above.
And you’ll be able to activate your Audirvana.
I opened Keychain and selected show expired certificated but don’t see anything.
Now here’s the weird thing. I still had APlus 2 on the Mac Mini and it launched just fine?