diff --git a/config_webrx.py b/config_webrx.py
index 37e87a7..4c57408 100644
--- a/config_webrx.py
+++ b/config_webrx.py
@@ -284,8 +284,6 @@ Note: if you experience audio underruns while CPU usage is 100%, you can:
 # using the auto squelch.
 #squelch_auto_margin = 10  # in dB
 
-nmux_memory = 50  # in megabytes. This sets the approximate size of the circular buffer used by nmux.
-
 #google_maps_api_key = ""
 
 # how long should positions be visible on the map?
diff --git a/owrx/config/defaults.py b/owrx/config/defaults.py
index ef03de0..37a1ee9 100644
--- a/owrx/config/defaults.py
+++ b/owrx/config/defaults.py
@@ -146,7 +146,6 @@ defaultConfig = PropertyLayer(
     waterfall_auto_min_range=50,
     tuning_precision=2,
     squelch_auto_margin=10,
-    nmux_memory=50,
     google_maps_api_key="",
     map_position_retention_time=2 * 60 * 60,
     decoding_queue_workers=2,
diff --git a/owrx/source/direct.py b/owrx/source/direct.py
index e51f0b8..d11d83b 100644
--- a/owrx/source/direct.py
+++ b/owrx/source/direct.py
@@ -13,10 +13,9 @@ class DirectSource(SdrSource, metaclass=ABCMeta):
         self.sleepOnRestart()
         self.start()
 
-    def getEventNames(self):
-        return super().getEventNames() + [
-            "nmux_memory",
-        ]
+    def nmux_memory(self):
+        # in megabytes. This sets the approximate size of the circular buffer used by nmux.
+        return 50
 
     def getNmuxCommand(self):
         props = self.sdrProps
@@ -24,13 +23,10 @@ class DirectSource(SdrSource, metaclass=ABCMeta):
         nmux_bufcnt = nmux_bufsize = 0
         while nmux_bufsize < props["samp_rate"] / 4:
             nmux_bufsize += 4096
-        while nmux_bufsize * nmux_bufcnt < props["nmux_memory"] * 1e6:
+        while nmux_bufsize * nmux_bufcnt < self.nmux_memory() * 1e6:
             nmux_bufcnt += 1
         if nmux_bufcnt == 0 or nmux_bufsize == 0:
-            raise ValueError(
-                "Error: nmux_bufsize or nmux_bufcnt is zero. "
-                "These depend on nmux_memory and samp_rate options in config_webrx.py"
-            )
+            raise ValueError("Error: unable to calculate nmux buffer parameters.")
 
         return [
             "nmux --bufsize %d --bufcnt %d --port %d --address 127.0.0.1"