WinGui: Handle auto-passthru correctly in the mixdown sanatising code.

diff --git a/win/CS/HandBrakeWPF/Services/Encode/Model/Models/AudioTrack.cs b/win/CS/HandBrakeWPF/Services/Encode/Model/Models/AudioTrack.cs
index 472eccb7f1c352d22e5707aca32c01e1e19e6e94..8d7047a5b24631fd2f872b6339f425db0957f4f3 100644 (file)
--- a/win/CS/HandBrakeWPF/Services/Encode/Model/Models/AudioTrack.cs
+++ b/win/CS/HandBrakeWPF/Services/Encode/Model/Models/AudioTrack.cs
@@ -125,7 +125,7 @@ namespace HandBrakeWPF.Services.Encode.Model.Models
             this.mixDown = track.MixDown != null ? track.MixDown.ShortName : "dpl2";
 
             // If the mixdown isn't supported, downgrade it.
-            if (encoderInfo != null && !HandBrakeEncoderHelpers.MixdownIsSupported(track.MixDown, encoderInfo, sourceTrack.ChannelLayout))
+            if (track.MixDown != null && encoderInfo != null && !HandBrakeEncoderHelpers.MixdownIsSupported(track.MixDown, encoderInfo, sourceTrack.ChannelLayout))
             {
                 HBMixdown changedMixdown = HandBrakeEncoderHelpers.GetDefaultMixdown(encoderInfo, (ulong)sourceTrack.ChannelLayout);
                 if (changedMixdown != null)