I had some problems with the combination of live TV and “long” standby time (more than 90 seconds):

I am using 2 Zotac Zboxes (AD10 with Fusion image, another different Zbox model with ION image) as clients and MediPortal as TV server. I use the latest updates of the modules.
I started with Openelec 3.0.3 and recognized the problems also with 3.0.4 and 3.0.5.

Basically TV works. TV server is running, I boot the powered-off Zbox, wait some seconds and start Live TV, e.g. via EPG timeline – everything OK.
Then i press the Zotac remote “0” button, it goes into standby mode.
After a few minutes, I start again with remote “1” button – also everything fine. I can repeat this multiple times.
Then I go into standby again, but for a longer time, e.g. 15 hours.
I wake up the box, start Live TV again and it displays “Working…” – but for at least 10 minutes! During this time the box hangs. In MP server, I can see the stream has already been active since I pressed the switch button.
If I don’t wait and reset the box, the server stream is not closed any more, and the TV card is blocked until I restart the MP service.
This behaviour happens with both Zboxes.

Solution / Workaround:

Seems like it is solved, at least for me, by a workaround.

I had to fix the following:
– Disable Spanning Tree at the managed network switch (or configure Fast Port)
– Storage read-only bug: I use an SD card for OE, the storage partition had to be converted to BTRFS, see wiki.openelec.tv/index.php?title=Using_B…he_storage_partition. Edit: If you get an fstab error when mounting the Storage partition, use the command like “mount -t btrfs /dev/sdb2 /mnt -o ssd”.
– (Remove any special characters from recordings and timeshifting shares, then restart MP server)
– (Replace TV server host name with IP in PVR client plugin)

In fact, in the end this workaround helped:
So this might be an SMB bug.