diff --git a/ohmpi/ohmpi.py b/ohmpi/ohmpi.py
index 59e72b252f8263dd58fe1d641c0d36e5d9748fc7..0d5427468ea574e630650bd23f6084ff008af918 100644
--- a/ohmpi/ohmpi.py
+++ b/ohmpi/ohmpi.py
@@ -518,9 +518,7 @@ class OhmPi(object):
         d = {}
         if self.switch_mux_on(quad, bypass_check=bypass_check, cmd_id=cmd_id):
             tx_volt = self._hw._compute_tx_volt(tx_volt=tx_volt, strategy=strategy, vmn_max=vmn_max)  # TODO: use tx_volt and vmn_max instead of hardcoded values
-            self._hw.switch_mux(electrodes=quad[0:2], roles=['A', 'B'], state='on')
-            time.sleep(0.5)
-            self._hw.switch_mux(electrodes=quad[0:2], roles=['A', 'B'], state='off')
+            time.sleep(0.5)  # to wait for pwr discharge
             self._hw.vab_square_wave(tx_volt, cycle_duration=injection_duration*2/duty_cycle, cycles=nb_stack, duty_cycle=duty_cycle)
             if 'delay' in kwargs.keys():
                 delay = kwargs['delay']