diff --git a/HISTORY b/HISTORY
index 051e23b..9ba250c 100644
--- a/HISTORY
+++ b/HISTORY
@@ -1,6 +1,8 @@
 VDR Plugin 'streamdev' Revision History
 ---------------------------------------
  
+- check availability of channel if VTP command TUNE is called without
+  prior PROV call (e.g. client side EPG scan)
 - added support for VDR 1.7.19 SignalStrength/SignalQuality
 - analog video channels use the same transponder and pid for different
   channels, so streamdev-client must always issue TUNE command
diff --git a/server/connectionVTP.c b/server/connectionVTP.c
index 64b5f37..8224d1d 100644
--- a/server/connectionVTP.c
+++ b/server/connectionVTP.c
@@ -1089,14 +1089,16 @@ bool cConnectionVTP::CmdTUNE(char *Opts)
 		return Respond(550, "Undefined channel \"%s\"", Opts);
 
 	if (chan != m_TuneChannel) {
-		esyslog("streamdev-server TUNE %s: Priority unknown - using 0", Opts);
+		isyslog("streamdev-server TUNE %s: Priority unknown - using 0", Opts);
 		prio = 0;
+		if (!ProvidesChannel(chan, prio))
+			return Respond(560, "Channel not available (ProvidesChannel)");
 	}
 	if ((dev = GetDevice(chan, prio)) == NULL)
-		return Respond(560, "Channel not available");
+		return Respond(560, "Channel not available (GetDevice)");
 
 	if (!dev->SwitchChannel(chan, false))
-		return Respond(560, "Channel not available");
+		return Respond(560, "Channel not available (SwitchChannel)");
 
 	delete m_LiveStreamer;
 	m_LiveStreamer = new cStreamdevLiveStreamer(prio, this);