[PROBLEM] DLNA database needs to be rebuilt every boot.

[TheOldPresbyope]

It may have to do with the fact that it's started before NAS source is mounted during moOde startup. Maybe it needs to have the source mounted before it starts??

when miniDLNA is stopped in UI its cache is also cleared which includes its database.

Yes..that describes the problem perfectly... cache is not kept between boots and miniDLNA starts ahead of the NAS in boot order.

Is there any downside to keeping the cache ? or linking its update to the library update ?

Is there a code line that could be commented  that would cancel the cache clearing..? just to try and see after a cold start if the clients would find the server.

"Is there any downside to keeping the cache ?" Dunno but...

A quick grep of 'minidlna' on the contents or /var/www flagged worker.php as the likely culprit. For clarity I've repeated the grep on just it:

Code:

pi@m8pi3a:/var/www/command $ grep -n minidlna worker.php
2067:        case 'minidlna':
2069:            sysCmd('systemctl stop minidlna');
2074:                syscmd('rm -rf /var/cache/minidlna/* > /dev/null');
2078:            sysCmd('systemctl stop minidlna');
2079:            syscmd('rm -rf /var/cache/minidlna/* > /dev/null');

This is PHP code. You can comment out lines 2074 and 2079 by prepending the double solidus (//). 

Good luck!

Regards,
Kent