fixes bug reading midi values

lib/voicemeeter/base.rb

@@ -209,11 +209,11 @@ module Voicemeeter
           exp: ->(x) { x >= 0 }
         )
       if (got_midi = res > 0)
-        vals = cmsg.read_string_bytes
+        vals = cmsg.read_string.bytes
         vals.each_slice(3) do |ch, key, velocity|
-          midi.channel = ch if midi.channel.nil? || midi.channel != ch
+          midi.channel = ch.to_i
           midi.current = key.to_i
-          midi.set(key.to_i, velocity.to_i)
+          midi.cache[key.to_i] = velocity.to_i
         end
       end
       got_midi

lib/voicemeeter/event.rb

@@ -18,7 +18,7 @@ module Voicemeeter
       def trigger(event)
         @callbacks.each do |callback|
           if callback.respond_to? :on_update
-            callback.on_update { event.to_s[3..] }
+            callback.on_update event.to_s[3..]
           elsif callback.name == event
             callback.call
           end

lib/voicemeeter/midi.rb

@@ -1,6 +1,7 @@
 module Voicemeeter
   class Midi
-    attr_accessor :cache, :current, :channel
+    attr_accessor :current, :channel
+    attr_reader :cache
 
     def initialize
       @cache = {}
@@ -9,9 +10,5 @@ module Voicemeeter
     def get(key)
       cache[key]
     end
-
-    def set(key, velocity)
-      cache[key] = velocity
-    end
   end
 end