The library is on a QNAP drive what has been fine for years and nothing has changed 

Unfortunately, most often “nothing has changed” is accurate from your perspective, but not from QNAPs, I suspect. My guess is that they’ve updated their firmware, and changed SMB v1 and NTML v1 without explicitly asking for your permission to do so. 

I’d certainly be looking rather strongly at the settings of the QNAP to make sure that it’s not now running SMB v3. 

I have experience, more than once, with Western Digital doing this to me.

Looking at the release notes you are correct QNAP have upgraded to SMB V2 as it is more secure, so I will have to find out how to go backwards to SMB V1.

But then at the same time why is Sonos only on SMB V1, or does it not allow the option for V1 or V2

Older S1 only units do not have enough hardware resources to run the SMB V2 client.

However, if you’re able to upgrade to S2, which means all your Sonos devices have more memory available, you can use SMB v2 or v3 as desired. 

Thanks it would be nice to but with 4 Play 5 speaker 2 Play 1 speakers 1 Connect also 2 Amps and a sound bar, it is not really and option that is easy to afford. But I am open to any suggestion's.

Full disclosure: I’m not a PLEX user, but it may be an option for you.

Hi there thanks, when i Looked at Plex last you had to upload all your stuff to there site  first, and I do not really want  to do that when I have my own server.