diff --git a/src/Miners/GMiner/GMiner.cs b/src/Miners/GMiner/GMiner.cs
index 733ea924f..39da28f8f 100644
--- a/src/Miners/GMiner/GMiner.cs
+++ b/src/Miners/GMiner/GMiner.cs
@@ -68,7 +68,7 @@ private string CreateCommandLine(string username)
 
             if (!_extraLaunchParameters.Contains("--dual_intensity") && _algorithmSecondType == AlgorithmType.Eaglesong)
             {
-                _extraLaunchParameters += "--dual_intensity 0";
+                _extraLaunchParameters += " --dual_intensity 0";
             }
 
             return cmd;
diff --git a/src/Miners/NBMiner/NBMiner.cs b/src/Miners/NBMiner/NBMiner.cs
index d5ec3ef42..531010481 100644
--- a/src/Miners/NBMiner/NBMiner.cs
+++ b/src/Miners/NBMiner/NBMiner.cs
@@ -151,7 +151,7 @@ private string CreateCommandLine(string username)
             var cmd = $"-a {AlgoName} -o {url} -u {username} -do nicehash+tcp://{url2} -du {username} --api 127.0.0.1:{_apiPort} {_devices} --no-watchdog {_extraLaunchParameters}";
             if (!_extraLaunchParameters.Contains("--secondary-intensity"))
             {
-                cmd += "--secondary-intensity 100";
+                cmd += " --secondary-intensity 100";
             }
             return cmd;
         }