diff --git a/hardware_system.py b/hardware_system.py
index 1e2fdfe7505561feffc8d9d0a9ae0d47930fdf32..ad80054557891e40c9eb1d8d6fbffcd3b831f77b 100644
--- a/hardware_system.py
+++ b/hardware_system.py
@@ -281,7 +281,7 @@ class OhmPiHardware:
             for i in range(len(electrodes)):
                 elec_dict[roles[i]].append(electrodes[i])
             mux_workers = []
-            for mux in self.mux_boards:
+            for _, mux in self.mux_boards.items():
                 # start a new thread to perform some work
                 mux_workers.append(Thread(target=mux.switch, kwargs={'elec_dict': elec_dict}))
             for mux_worker in mux_workers:
diff --git a/test_mux_2024.py b/test_mux_2024.py
index 5c12546bea2bc99bb26213b7ed84b52a7cba8ee3..d125f0f26839e3806328a9e16ff3a5b98f231ebb 100644
--- a/test_mux_2024.py
+++ b/test_mux_2024.py
@@ -19,7 +19,7 @@ time.sleep(8)
 #mux.switch({'A': [1], 'B': [4], 'M': [2], 'N': [3]}, state='off')
 mux.reset()
 mux.test({'A': [9, 10, 11, 12, 13, 14, 15, 16], 'B': [9, 10, 11, 12, 13, 14, 15, 16],
-          'M': [9, 10, 11, 12, 13, 14, 15, 16], 'N': [9, 10, 11, 12, 13, 14, 15, 16]}, activation_time=.25)
+          'M': [9, 10, 11, 12, 13, 14, 15, 16], 'N': [9, 10, 11, 12, 13, 14, 15, 16]}, activation_time=.1)
 
 # mux as part of a OhmPiHardware system
 from OhmPi.hardware_system import OhmPiHardware