Router SMB3 support

Admin specs tell me that my router is 'Nighthawk AX5 RAX30'. I have a USB drive connected to this router. Drive is accessible, via ReadyShare, from my Windows 11 PC on my home network; no problems. (That is, I can view, read, write, delete files on the drive from Windows Explorer, Word, Excel, etc.)

However, an app (Sonos) needs to access music files on the drive, and after a recent update it is failing to do so. I suspect that this is because the app is now using SMB3 and the router only supports SMB1.

1. How can I verify that the router is using SMB1?

2. Is the router upgradeable to SMB3? (I suspect not.)

3. Is there a Netgear router that does support SMB3, with similar specs to the RAX30, to which I can upgrade?