Undefined index: picture at

Hi …
I have a huge MusicBase < 220K including a lots of Dupes because Sampler etc.
I have had in php.ini 600M and audioplayer didn’t work because memory. Now I have 756M and it is starting the scanning but stops at round about 160 Title. After a while I’ve got the message new files and I get another ~ 160 Titles.
But the folder.jpg (same saved in Tag) are messed up.

I have in NC LOG following Message 10 Times per second !!!
Undefined index: picture at /var/www/nextcloud/apps/audioplayer/lib/Controller/ScannerController.php#558

All Files are up to date, no Beta, but Redis is not working because PHP 7.0 I guess. Ubuntu 16.04 LTS in Hyper-V VM
Music files are at the Host NTFS Drive mounted in fstab

All files are stored in one Folder. Artist is subfolder, XXXX-Album and CD1 to CDX if needed.
Inside the Album folder is folder.jpg for Album Art and also the Album Art is stored in MP3tag and FLAC etc. if available I have another subfolder in XXXX-Album for the Artwork.

Any Ideas?

Thanks for help.

I have scanned a single Artist Folder, that is working but I got this message

imagecreatefromjpeg(): gd-jpeg: JPEG library reports unrecoverable error: Unsupported marker type 0xdf at /var/www/nextcloud/lib/private/legacy/image.php#572

That are ALAC Files *.m4a


sorry for the late reply. the undefined index is fixed with the newly released 2.5.0