Slow iTunes sync

It really makes me sad. I just bought an iPhone 8 with 256gb. I have my library sitting on an SMB drive, accessible via DFS. Regular data transfer works like a charm.

What's not working or poorly working is iTunes sync. After the iPhone replacement it took me almost a week to resync my music content. It seem pretty much pointless of having a huge data space when Apple cannot handle the simple file transfer / sync properly.

BTW, I have tried it on OSX and Windows 10. Same effect! - So don't bother us with "try resetting blablabla". Get finally your work done and deliver what should have delivered for a 1000$ device!!

R.