diff --git a/SdrsDecoder.Cli/Program.cs b/SdrsDecoder.Cli/Program.cs
index 4f2537e..642dcb7 100644
--- a/SdrsDecoder.Cli/Program.cs
+++ b/SdrsDecoder.Cli/Program.cs
@@ -43,6 +43,8 @@ static void Main(string[] args)
                     samples.Add(s);
                 }
 
+                var baud = 1200;
+
                 //var sr = file.WaveFormat.SampleRate;
 
                 //var i = 256;
@@ -87,7 +89,7 @@ static void Main(string[] args)
                 //}
 
                 var chain = new PocsagChain(
-                    1200,
+                    baud,
                     file.WaveFormat.SampleRate,
                     (message) =>
                     {
diff --git a/SdrsDecoder/Flex/FlexChain.cs b/SdrsDecoder/Flex/FlexChain.cs
index e8c6e93..37560e1 100644
--- a/SdrsDecoder/Flex/FlexChain.cs
+++ b/SdrsDecoder/Flex/FlexChain.cs
@@ -1,6 +1,7 @@
 using SdrsDecoder.Support;
 using System;
 using System.Collections.Generic;
+using System.Numerics;
 
 namespace SdrsDecoder.Flex
 {
@@ -20,21 +21,19 @@ public FlexChain(float baud, float sampleRate, Action<MessageBase> messageReceiv
         {
             this.baud = baud;
 
-            
+            var targetRate = (int)this.baud * 10;
+            var gcd = (int)BigInteger.GreatestCommonDivisor((BigInteger)sampleRate, (BigInteger)targetRate);
 
-            var i = 1;
-            var d = 1;
+            // TODO: refactor this stuff
 
-            if (baud == 1600)
-            {
-                i = 32;
-                d = 75;
-            }
+            int i = targetRate / gcd;
+            int d = (int)sampleRate / gcd;
 
-            if (baud == 3200)
+            // if I gets too big then filtering / performance becomes an issue
+            if (i > 100)
             {
-                i = 64;
-                d = 75;
+                i = 1;
+                d = 1;
             }
 
             var isr = sampleRate * i;
diff --git a/SdrsDecoder/Pocsag/PocsagChain.cs b/SdrsDecoder/Pocsag/PocsagChain.cs
index 6144879..ca29a94 100644
--- a/SdrsDecoder/Pocsag/PocsagChain.cs
+++ b/SdrsDecoder/Pocsag/PocsagChain.cs
@@ -1,5 +1,6 @@
 using SdrsDecoder.Support;
 using System;
+using System.Numerics;
 
 namespace SdrsDecoder.Pocsag
 {
@@ -20,19 +21,18 @@ public PocsagChain(float baud, float sampleRate, Action<MessageBase> messageRece
         {
             this.baud = baud;
 
-            var i = 1;
-            var d = 1;
+            // TODO: refactor this and stuff in flexchain
+            var targetRate = (int)this.baud * 10;
+            var gcd = (int)BigInteger.GreatestCommonDivisor((BigInteger)sampleRate, (BigInteger)targetRate);
 
-            if (baud == 1200)
-            {
-                i = 8;
-                d = 25;
-            }
+            int i = targetRate / gcd;
+            int d = (int)sampleRate / gcd;
 
-            if (baud == 2400)
+            // if I gets too big then filtering / performance becomes an issue
+            if (i > 100)
             {
-                i = 16;
-                d = 25;
+                i = 1;
+                d = 1;
             }
 
             var isr = sampleRate * i;