Connection Interrupts with movies and music files

Hello,

Sorry for bad english^^
hopefully someone can help me. On OMV 4 im getting weird connection Interrupts, mostly when watching movies or listening to music....
I tried different Media Players, its the same problem. I start the playback and it runs for 2-10 Minutes, then it stops. Taskmanager shows that theres no traffic then to the nas. The player hangs as also the file manager (Nemo).
But when i access the NAS via rdp connection an virtual machine (virtualbox+remmina) or when i open the webgui of ovm, it resumes playback, nemo also works again.

I run only 2 Clients with Linux Mint 19, one Windows 7 VM installed on the NAS, one Windows 7 Client.
I did not check if the problem also exists on the WIndows 7 Clients.
On the Linux Clients the Shares are mounted via Smb4K, i also tried to set the SMB Version to SMB3 here.

I also tried this options in the extra section with no success:

socket options = TCP_NODELAY SO_RCVBUF=65536 SO_SNDBUF=65536


read raw = yes 


write raw = yes 


max xmit = 65535 


dead time = 15


getwd cache = yes

Data of NAS:

AMD Athlon X2 5000+
4 GB RAM
3 Sata HDDs
1 SSD with OMV installed


OMV: 4.1.10
Kernel: 4.17.0-0


IP-Adress: Static

I have ssh access to the NAS system for monitoring via ksysguard, ram and cpu looks good, i dont think i have a bottleneck here.

Thanks for the help.

EDIT:
I got an error when setting the omv version in the forum.
Exception ID: b9fc21e5910c9eab00ac4d94e44de2074072e389