Here's the situation: All my library files are shared across my network using a samba share on my NAS. My HTPC is connected via wire to the switch the NAS is also connected to.
Now everytime I resume standby after a longer period, I get the "file not found, do you want to remove it from the library?"-dialog. If I try to play the file again, right after having clicked "No", it always plays. After that, playing every other file also works without a problem. Even when I enter standby again and resume right after that, it works.
The problem only exists after longer periods of standby.
Another important info: The NAS is NOT in standby and there doesn't seem to be a timeout issue: The dialog appears right away, without waiting the 20 seconds I defined in advancedsettings.xml:
When the NAS is indeed in standby, XBMC waits until it woke up and then plays the selected file like a charm.
Debug Log: http://pastebin.com/XR9iSrgs
Here's what I did: Resumed from standby, enabled debugging, went to "TV shows", tried to play an episode, got the dialog, clicked "No", immediately tried to play the same episode again, it played, stopped the playback, disabled debugging.
As you can see, I added my NAS as a source with a hostname instead of an IP, so I can change it easier in the future.
This is how I entered the hostname in my /etc/hosts file:
192.168.0.3 HTPC.localdomain HTPC
192.168.0.2 NAS.localdomain NAS
I hope you guys can make something from the information I gave. If not, please tell me what ever might be missing!