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Emby.Server.Implementations/LiveTv/TunerHosts/BaseTunerHost.cs

@@ -83,8 +83,9 @@ namespace Emby.Server.Implementations.LiveTv.TunerHosts
                 try
                 {
                     var channels = await GetChannels(host, enableCache, cancellationToken).ConfigureAwait(false);
+                    var newChannels = channels.Where(i => !list.Any(l => string.Equals(i.Id, l.Id, StringComparison.OrdinalIgnoreCase)));
 
-                    list.AddRange(channels);
+                    list.AddRange(newChannels);
 
                     if (!enableCache)
                     {