fix RW/FF NUD (fixes #2061)

src/BizHawk.Client.EmuHawk/config/SoundConfig.Designer.cs

@@ -122,6 +122,7 @@
             0,
             0,
             0});
+			this.nudRWFF.ValueChanged += new System.EventHandler(this.nudRWFF_ValueChanged);
 			// 
 			// cbEnableRWFF
 			// 

src/BizHawk.Client.EmuHawk/config/SoundConfig.cs

@@ -148,5 +148,10 @@ namespace BizHawk.Client.EmuHawk
 		{
 			UpdateSoundDialog();
 		}
+
+		private void nudRWFF_ValueChanged(object sender, EventArgs e)
+		{
+			tbRWFF.Value = (int)nudRWFF.Value;
+		}
 	}
 }