diff --git a/python/trx/radio_if.py b/python/trx/radio_if.py
index 355312b..119b237 100644
--- a/python/trx/radio_if.py
+++ b/python/trx/radio_if.py
@@ -257,6 +257,12 @@
 			(self.dict_toggle_sign, 'dict_out'),
 			(self.msg_to_tag_sink, 'msg'))
 
+
+		# Some UHD devices (such as UmTRX) do start the clock
+		# not from 0, so it's required to reset it manually.
+		# Resetting UHD source will also affect the sink.
+		self.phy_src.set_time_now(uhd.time_spec(0.0))
+
 	def shutdown(self):
 		print("[i] Shutdown Radio interface")
 		self.stop()