diff --git a/Moose Development/Moose/Sound/SRS.lua b/Moose Development/Moose/Sound/SRS.lua
index 559d23c56..134c2780d 100644
--- a/Moose Development/Moose/Sound/SRS.lua	
+++ b/Moose Development/Moose/Sound/SRS.lua	
@@ -516,8 +516,20 @@ end
 -- @return #MSRS self
 function MSRS:SetBackend(Backend)
   self:F( {Backend=Backend} )
-  self.backend=Backend or MSRS.Backend.SRSEXE
-
+  Backend = Backend or MSRS.Backend.SRSEXE -- avoid nil
+  local function Checker(back)
+    local ok = false
+    for _,_backend in pairs(MSRS.Backend) do
+      if tostring(back) == _backend then ok = true end
+    end
+    return ok
+  end
+  
+  if Checker(Backend) then  
+    self.backend=Backend 
+  else    
+    MESSAGE:New("ERROR: Backend "..tostring(Backend).." is not supported!",30,"MSRS",true):ToLog():ToAll()    
+  end 
   return self
 end
 
@@ -1184,8 +1196,8 @@ end
 -- @param Core.Point#COORDINATE Coordinate Coordinate.
 -- @return #MSRS self
 function MSRS:PlayTextExt(Text, Delay, Frequencies, Modulations, Gender, Culture, Voice, Volume, Label, Coordinate)
-  self:F( {Text, Delay, Frequencies, Modulations, Gender, Culture, Voice, Volume, Label, Coordinate} )
-
+  self:T(( {Text, Delay, Frequencies, Modulations, Gender, Culture, Voice, Volume, Label, Coordinate} )
+  self:T((self.lid.."Backend "..self.backend)
   if Delay and Delay>0 then
     self:ScheduleOnce(Delay, MSRS.PlayTextExt, self, Text, 0, Frequencies, Modulations, Gender, Culture, Voice, Volume, Label, Coordinate)
   else
@@ -1205,6 +1217,7 @@ function MSRS:PlayTextExt(Text, Delay, Frequencies, Modulations, Gender, Culture
       self:_ExecCommand(command)
 
     elseif self.backend==MSRS.Backend.GRPC then
+      BASE:I("MSRS.Backend.GRPC")
 
       self:_DCSgRPCtts(Text, Frequencies, Gender, Culture, Voice, Volume, Label, Coordinate)
 
@@ -1831,7 +1844,7 @@ end
 -- @param #MSRSQUEUE self
 -- @return #MSRSQUEUE self The MSRSQUEUE object.
 function MSRSQUEUE:Clear()
-  self:I(self.lid.."Clearing MSRSQUEUE")
+  self:T((self.lid.."Clearing MSRSQUEUE")
   self.queue={}
   return self
 end
@@ -1842,7 +1855,6 @@ end
 -- @param #MSRSQUEUE.Transmission transmission The transmission data table.
 -- @return #MSRSQUEUE self
 function MSRSQUEUE:AddTransmission(transmission)
-
   -- Init.
   transmission.isplaying=false
   transmission.Tstarted=nil
@@ -1921,20 +1933,20 @@ function MSRSQUEUE:NewTransmission(text, duration, msrs, tstart, interval, subgr
   transmission.Tplay=tstart or timer.getAbsTime()
   transmission.subtitle=subtitle
   transmission.interval=interval or 0
-  transmission.frequency=frequency
-  transmission.modulation=modulation
+  transmission.frequency=frequency or msrs.frequencies
+  transmission.modulation=modulation or msrs.modulations
   transmission.subgroups=subgroups
   if transmission.subtitle then
     transmission.subduration=subduration or transmission.duration
   else
     transmission.subduration=0 --nil
   end
-  transmission.gender = gender
-  transmission.culture = culture
-  transmission.voice = voice
-  transmission.volume = volume
-  transmission.label = label
-  transmission.coordinate = coordinate
+  transmission.gender = gender or msrs.gender
+  transmission.culture = culture or msrs.culture
+  transmission.voice = voice or msrs.voice
+  transmission.volume = volume or msrs.volume
+  transmission.label = label or msrs.Label
+  transmission.coordinate = coordinate or msrs.coordinate
 
   -- Add transmission to queue.
   self:AddTransmission(transmission)
@@ -1946,7 +1958,8 @@ end
 -- @param #MSRSQUEUE self
 -- @param #MSRSQUEUE.Transmission transmission The transmission.
 function MSRSQUEUE:Broadcast(transmission)
-
+  self:T((self.lid.."Broadcast")
+  
   if transmission.frequency then
     transmission.msrs:PlayTextExt(transmission.text, nil, transmission.frequency, transmission.modulation, transmission.gender, transmission.culture, transmission.voice, transmission.volume, transmission.label, transmission.coordinate)
   else
@@ -2115,7 +2128,7 @@ function MSRSQUEUE:_CheckRadioQueue(delay)
     -- Found a new transmission.
     if next~=nil and not playing then
       -- Debug info.
-      self:T(self.lid..string.format("Broadcasting text=\"%s\" at T=%.3f", next.text, time))
+      self:T((self.lid..string.format("Broadcasting text=\"%s\" at T=%.3f", next.text, time))
 
       -- Call SRS.
       self:Broadcast(next)