Hi @xium,
Have you tried using other devices as your viewer to see if the issue also happens there?
Also, for further analysis of the issue, please send us the logs of your server machine by opening the spacedesk Driver console and clicking on Diagnostics then follow the steps below:
1. Download the DebugView.
2. Check the Diagnostic Collection box.
3. Reproduce the issue e.g. by connecting the spacedesk Viewer app with your S9 FE+.
4. Uncheck the Diagnostic Collection box.
5. Click “Save All Information” button (this might take a while to finish).
6. Compress/Zip the folder which contains the logs, then attach to your next reply to this post.
If the file size exceeds 512 KB, you may upload it to Dropbox then include the download link on your next reply.
Thanks!