Index: TVLibrary/TVLibrary/Implementations/DVB/ConditionalAccess/ConditionalAccess.cs
===================================================================
--- TVLibrary/TVLibrary/Implementations/DVB/ConditionalAccess/ConditionalAccess.cs	(revision 26914)
+++ TVLibrary/TVLibrary/Implementations/DVB/ConditionalAccess/ConditionalAccess.cs	(working copy)
@@ -825,10 +825,11 @@
     }
 
     /// <summary>
-    /// Sets the DVB s2 modulation.
+    /// Sets the DVB-S2 parameters such as modulation, roll-off, pilot etc.
     /// </summary>
-    /// <param name="parameters">The parameters.</param>
-    /// <param name="channel">The channel.</param>
+    /// <param name="parameters">The LNB parameters.</param>
+    /// <param name="channel">The channel to tune.</param>
+    /// <returns>The channel with DVB-S2 parameters set.</returns>
     public DVBSChannel SetDVBS2Modulation(ScanParameters parameters, DVBSChannel channel)
     {
       //Log.Log.WriteFile("Trying to set DVB-S2 modulation...");
@@ -983,7 +984,6 @@
             //Log.Log.WriteFile("DigitalEverywhere: we're tuning DVB-S, pilot & roll-off are now not set");
           }
 
-          DVBSChannel tuneChannel = new DVBSChannel(channel);
           if (channel.InnerFecRate != BinaryConvolutionCodeRate.RateNotSet)
           {
             //Set the DigitalEverywhere binary values for Pilot & Roll-off
@@ -1000,13 +1000,14 @@
             if (channel.Rolloff == RollOff.ThirtyFive)
               _rollOff = 48;
             //The binary values get added to the current InnerFECRate - done!
-            tuneChannel.InnerFecRate = channel.InnerFecRate + _pilot + _rollOff;
+            BinaryConvolutionCodeRate r = channel.InnerFecRate + _pilot + _rollOff;
+            channel.InnerFecRate = r;
           }
           Log.Log.WriteFile("DigitalEverywhere DVB-S2 modulation set to:{0}", channel.ModulationType);
           Log.Log.WriteFile("DigitalEverywhere Pilot set to:{0}", channel.Pilot);
           Log.Log.WriteFile("DigitalEverywhere RollOff set to:{0}", channel.Rolloff);
-          Log.Log.WriteFile("DigitalEverywhere fec set to:{0}", (int)tuneChannel.InnerFecRate);
-          return tuneChannel;
+          Log.Log.WriteFile("DigitalEverywhere fec set to:{0}", (int)channel.InnerFecRate);
+          return channel;
         }
       }
       catch (Exception ex)
Index: TVLibrary/TVLibrary/Implementations/DVB/Graphs/DVBS/TvCardDVBS.cs
===================================================================
--- TVLibrary/TVLibrary/Implementations/DVB/Graphs/DVBS/TvCardDVBS.cs	(revision 26914)
+++ TVLibrary/TVLibrary/Implementations/DVB/Graphs/DVBS/TvCardDVBS.cs	(working copy)
@@ -332,19 +332,25 @@
         locator.put_CarrierFrequency((int)dvbsChannel.Frequency);
         dvbsLocator.put_SymbolRate(dvbsChannel.SymbolRate);
         dvbsLocator.put_SignalPolarisation(dvbsChannel.Polarisation);
-        //DVB-S2 specific modulation class call here if DVB-S2 card detected
-        DVBSChannel tuneChannel = dvbsChannel;
+
+        // Set DVB-S2 and manufacturer specific tuning parameters here.
+        //-------------------------------------------------------------------
+        // Important: the original dvbsChannel object *must not* be modified
+        // otherwise IsDifferentTransponder() will sometimes returns true
+        // when it shouldn't. See mantis 0002979.
+        //-------------------------------------------------------------------
+        DVBSChannel tuneChannel = new DVBSChannel(dvbsChannel);
         if (_conditionalAccess != null)
         {
-          tuneChannel = _conditionalAccess.SetDVBS2Modulation(_parameters, dvbsChannel);
+          tuneChannel = _conditionalAccess.SetDVBS2Modulation(_parameters, tuneChannel);
         }
         dvbsLocator.put_Modulation(tuneChannel.ModulationType);
         Log.Log.WriteFile("dvbs:channel modulation is set to {0}", tuneChannel.ModulationType);
         dvbsLocator.put_InnerFECRate(dvbsChannel.InnerFecRate);
         Log.Log.WriteFile("dvbs:channel FECRate is set to {0}", tuneChannel.InnerFecRate);
         _tuneRequest.put_Locator(locator);
+
         //set the DisEqC parameters 
-
         if (_conditionalAccess != null)
         {
           //int hr2 = ((IMediaControl)_graphBuilder).Pause();