diff --git a/src/PRDevice.cpp b/src/PRDevice.cpp
index 6bda82b..9e57817 100644
--- a/src/PRDevice.cpp
+++ b/src/PRDevice.cpp
@@ -58,7 +58,7 @@ PRDevice* PRDevice::Create(PRMachineType machineType)
         return NULL;
     }
 
-    if (machineType != dev->GetReadMachineType())
+    if (machineType != kPRMachineCustom && machineType != dev->GetReadMachineType())
     {
         dev->Close();
         return NULL;