I experience the same problem with LibreELEC 7.0.3 and my Samsung TV (UE46F6470). Here's an excerpt from my log file with CEC debugging activated, at the moment I turned on my TV again:
Code
21:20:31 T:2971837344 DEBUG: CecLogMessage - >> 0f:32:67:65:72
21:20:31 T:2971837344 DEBUG: CecLogMessage - >> TV (0) -> Broadcast (F): set menu language (32)
21:20:34 T:2971837344 DEBUG: CecLogMessage - >> 0f:80:00:00:10:00
21:20:34 T:2971837344 DEBUG: CecLogMessage - making Recorder 1 (1) the active source
21:20:34 T:2971837344 DEBUG: CecLogMessage - >> source activated: Recorder 1 (1)
21:20:34 T:2971837344 DEBUG: CecLogMessage - sending active source message for 'Recorder 1'
21:20:34 T:2971837344 DEBUG: CecLogMessage - << powering on 'TV' (0)
21:20:34 T:2971837344 DEBUG: CecLogMessage - << 10:04
21:20:34 T:2971837344 DEBUG: CecLogMessage - >> TV (0) -> Broadcast (F): routing change (80)
21:20:34 T:2971837344 DEBUG: CecLogMessage - << Recorder 1 (1) -> broadcast (F): active source (1000)
21:20:34 T:2971837344 DEBUG: CecLogMessage - << 1f:82:10:00
21:20:34 T:2971837344 DEBUG: CecLogMessage - << Recorder 1 (1) -> TV (0): menu state 'activated'
21:20:34 T:2971837344 DEBUG: CecLogMessage - << 10:8e:00
21:20:35 T:2971837344 DEBUG: CecLogMessage - >> 4f:84:30:00:04
21:20:35 T:2971837344 DEBUG: CecLogMessage - >> Playback 1 (4) -> Broadcast (F): report physical address (84)
21:20:37 T:2971837344 DEBUG: CecLogMessage - >> 0f:85
21:20:37 T:2971837344 DEBUG: CecLogMessage - >> 0 requests active source
21:20:37 T:2971837344 DEBUG: CecLogMessage - << Recorder 1 (1) -> broadcast (F): active source (1000)
21:20:37 T:2971837344 DEBUG: CecLogMessage - << 1f:82:10:00
21:20:37 T:2971837344 DEBUG: CecLogMessage - >> TV (0) -> Broadcast (F): request active source (85)It's interesting that Kodi tries to send an active source message even though I deactivated all corresponding options in Settings -> System -> Input devices -> libcec. Looks like a bug in Kodi to me...
Cheers
Thomas