diff --git a/boswatch/decoder/fms.py b/boswatch/decoder/fms.py
index e7ba783..abf9554 100644
--- a/boswatch/decoder/fms.py
+++ b/boswatch/decoder/fms.py
@@ -35,7 +35,7 @@ class Fms:
         logging.debug("FMS decoder started")
 
     @staticmethod
-    def decode(self, data):
+    def decode(data):
         """!Decodes FMS
 
         @param data: FMS for decoding
diff --git a/boswatch/decoder/pocsag.py b/boswatch/decoder/pocsag.py
index e3adb28..2f81a98 100644
--- a/boswatch/decoder/pocsag.py
+++ b/boswatch/decoder/pocsag.py
@@ -35,7 +35,7 @@ class Pocsag:
         logging.debug("POCSAG decoder started")
 
     @staticmethod
-    def decode(self, data):
+    def decode(data):
         """!Decodes POCSAG
 
         @param data: POCSAG for decoding
diff --git a/boswatch/decoder/zvei.py b/boswatch/decoder/zvei.py
index 2224045..7e706de 100644
--- a/boswatch/decoder/zvei.py
+++ b/boswatch/decoder/zvei.py
@@ -36,7 +36,7 @@ class Zvei:
         logging.debug("ZVEI decoder started")
 
     @staticmethod
-    def decode(self, data):
+    def decode(data):
         """!Decodes ZVEI
 
         @param data: ZVEI for decoding
@@ -46,7 +46,7 @@ class Zvei:
 
             bwPacket = packet.Packet()
             bwPacket.setField("mode", "zvei")
-            bwPacket.setField("zvei", self._solveDoubleTone(data[7:12]))
+            bwPacket.setField("zvei", Zvei._solveDoubleTone(data[7:12]))
 
             logging.debug(bwPacket)
             return bwPacket