diff --git a/fhem/FHEM/72_FRITZBOX.pm b/fhem/FHEM/72_FRITZBOX.pm
index f0a13dd8d..7e768cd13 100644
--- a/fhem/FHEM/72_FRITZBOX.pm
+++ b/fhem/FHEM/72_FRITZBOX.pm
@@ -1151,7 +1151,7 @@ sub FRITZBOX_SetMOH($@)
    my @cmdArray;
    my $result;
    my $name = $hash->{NAME};
-   my $uploadFile = '/var/tmp/moh_upload';
+   my $uploadFile = '/var/tmp/moh_upload.mp3';
    my $mohFile = '/var/tmp/fx_moh';
 
    if (lc $type eq lc $mohtype[0] || $type eq "0")