I dont have as big of a library as yours (only 275K) but I’ve run roon for many years on many platforms so have seen lots of things that will break playback so just trying to get the whole picture - others will also chime in here too. sometimes a picture paints more than words can adequately convey.
we are all just trying to help you here so hope you can suffer our interest 
All. Thanks for the help. I was curious as to why so I could learn. I think you misunderstood my last email.
if you are in Singapore I would just offer to drop over…offer stands if you are tho.
All the remotes use the same server database. The local install may have a problem but I believe you have reinstalled so that shouldn’t be an issue.
Thanks I am in the Us.
The Local install of the remote?
If there was a corrupt database it would more likely be on the core, however as stuff plays on the phone that doesn’t seem to apply.
The remote installs themselves may be corrupt but I would expect immediate failure in that case.
I would take Danny’s advice and start over with a small segment of your library and go from there. That may solve whatever the problem is and then, you can start adding back to your library or keep it on multiple drives, etc.