diff --git a/spikeinterface/core/baserecording.py b/spikeinterface/core/baserecording.py
index 7afd5506a9..82e9cefd91 100644
--- a/spikeinterface/core/baserecording.py
+++ b/spikeinterface/core/baserecording.py
@@ -1,5 +1,6 @@
 from typing import Iterable, List, Union
 from pathlib import Path
+import warnings
 
 import numpy as np
 
@@ -103,6 +104,13 @@ def get_traces(self,
             assert order in ["C", "F"]
             traces = np.asanyarray(traces, order=order)
         if return_scaled:
+            if hasattr(self, "NeoRawIOClass"):
+                if self.has_non_standard_units:
+                    message = ( 
+                    f'This extractor based on neo.{self.NeoRawIOClass} has channels with units not in (V, mV, uV)'
+                    )
+                    warnings.warn(message)
+            
             if not self.has_scaled_traces():
                 raise ValueError('This recording do not support return_scaled=True (need gain_to_uV and offset_'
                                  'to_uV properties)')
diff --git a/spikeinterface/extractors/neoextractors/neobaseextractor.py b/spikeinterface/extractors/neoextractors/neobaseextractor.py
index 4d023a45c9..a5b661b001 100644
--- a/spikeinterface/extractors/neoextractors/neobaseextractor.py
+++ b/spikeinterface/extractors/neoextractors/neobaseextractor.py
@@ -64,11 +64,12 @@ def __init__(self, stream_id=None, all_annotations=False, **neo_kwargs):
         offsets = signal_channels['offset']
 
         units = signal_channels['units']
-        if not np.all(np.isin(units, ['V', 'Volt', 'mV', 'uV'])):
-            # check that units are V, mV or uV
-            message = f'This extractor based on  neo.{self.NeoRawIOClass} have strange units not in (V, mV, uV) {units}'
-            warnings.warn(message)
         
+        # mark that units are V, mV or uV
+        self.has_non_standard_units = False
+        if not np.all(np.isin(units, ['V', 'Volt', 'mV', 'uV'])):
+            self.has_non_standard_units = True
+
         additional_gain = np.ones(units.size, dtype='float')
         additional_gain[units == 'V'] = 1e6
         additional_gain[units == 'Volt'] = 1e6