So, like many, I have older S1 SMBv1 compatible units that can no longer access shared drives on my NAS, even if I enable SMBv1 on the NAS. I was frustrated and had read many on here with the same issues and frustrations. So I set about finding a way around this.
My solution will not work for everyone (I know, sorry) but those with a compatible NAS should be able to do this.
What worked for me.
I run TrueNas on my Beelink NAS. (It’s available as a installable package on many NAS brands) I installed Plex server on my NAS and configured it to run a media server on my local network only. I then added the Plex music service to my old S1 devices and now have access to all my music again! Here’s a video to help with the setup of Plex on the NAS. I only have the free version of Plex and it is working fine, so far.
I hope that helps some of you! I was getting really annoyed not being able to access my music since I upgraded my storage but as the saying goes “there are no problems, only solutions” Good luck!
Plex on S1 app on my mobile showing access to my music library on the NAS again

Adding the path to the Plex app in the NAS config page, all in the linked video

Music server access

Application running on TrueNas
