diff --git a/gprMax/contexts.py b/gprMax/contexts.py
index 708b4fe9..66828dc8 100644
--- a/gprMax/contexts.py
+++ b/gprMax/contexts.py
@@ -130,7 +130,9 @@ class MPIContext(Context):
         model_config = config.ModelConfig()
         # Set GPU deviceID according to worker rank
         if config.sim_config.general["solver"] == "cuda":
-            model_config.device = {"dev": config.sim_config.devices["devs"][self.rank - 1], "snapsgpu2cpu": False}
+            model_config.device = {"dev": config.sim_config.devices["devs"][self.rank - 1], 
+                                   "deviceID": self.rank - 1,
+                                   "snapsgpu2cpu": False}
         config.model_configs = model_config
 
         G = create_G()