diff --git a/fhem/CHANGED b/fhem/CHANGED
index 5fb21cf50..a107b8219 100644
--- a/fhem/CHANGED
+++ b/fhem/CHANGED
@@ -1,5 +1,6 @@
 # Add changes at the top of the list. Keep it in ASCII, and 80-char wide.
 # Do not insert empty lines here, update check depends on it.
+ - bugfix:  70_DENON_AVR: handled some uninitialized values
  - new:     72_UBUS_CALL: module to send call requests via uBus client
  - new:     72_UBUS_CLIENT: module to communicate with uBus devices
  - bugfix:  88_HMCCU: bugfixes and improvements
diff --git a/fhem/FHEM/70_DENON_AVR.pm b/fhem/FHEM/70_DENON_AVR.pm
index 7aaa33d7c..bfc703f4d 100755
--- a/fhem/FHEM/70_DENON_AVR.pm
+++ b/fhem/FHEM/70_DENON_AVR.pm
@@ -1531,7 +1531,7 @@ DENON_AVR_Read($)
 	my $state = ReadingsVal( $name, "power", "off" );
 	my $buf = '';
 	my $zone = 0;
-	my $return;
+	my $return = '';
 	
 	if(defined($hash->{helper}{PARTIAL}) && $hash->{helper}{PARTIAL}) {
 	$buf = $hash->{helper}{PARTIAL} . DevIo_SimpleRead($hash);
@@ -1761,6 +1761,7 @@ DENON_AVR_Parse(@)
 			if($2 eq 'ON' || $2 eq 'OFF')
 			{
 				my $status = DENON_GetValue('PS', $1);
+                                $status = "unknown" unless defined($status);
 				readingsBulkUpdate($hash, $status, lc($2)) if($status ne "unknown");
 				$return = $status." ".lc($2);
 			}