Possibly fix mute & deaf state for guild users (#3070)

src/Discord.Net.WebSocket/Entities/Users/SocketGuildUser.cs

@@ -24,6 +24,9 @@ public class SocketGuildUser : SocketUser, IGuildUser
         private long? _joinedAtTicks;
         private ImmutableArray<ulong> _roleIds;
 
+        private bool? _isDeafened;
+        private bool? _isMuted;
+
         internal override SocketGlobalUser GlobalUser { get; set; }
         /// <summary>
         ///     Gets the guild the user is in.
@@ -66,9 +69,9 @@ public class SocketGuildUser : SocketUser, IGuildUser
         /// <inheritdoc />
         public bool IsSuppressed => VoiceState?.IsSuppressed ?? false;
         /// <inheritdoc />
-        public bool IsDeafened => VoiceState?.IsDeafened ?? false;
+        public bool IsDeafened => VoiceState?.IsDeafened ?? _isDeafened ?? false;
         /// <inheritdoc />
-        public bool IsMuted => VoiceState?.IsMuted ?? false;
+        public bool IsMuted => VoiceState?.IsMuted ?? _isMuted ?? false;
         /// <inheritdoc />
         public bool IsStreaming => VoiceState?.IsStreaming ?? false;
         /// <inheritdoc />
@@ -191,6 +194,11 @@ internal void Update(ClientState state, MemberModel model)
             if (model.Banner.IsSpecified)
                 GuildBannerHash = model.Banner.Value;
 
+            if (model.Mute.IsSpecified)
+                _isMuted = model.Mute.Value;
+            if (model.Deaf.IsSpecified)
+                _isDeafened = model.Deaf.Value;
+
             Flags = model.Flags;
         }
         internal void Update(ClientState state, PresenceModel model, bool updatePresence)