diff --git a/python/valis/io/spectra.py b/python/valis/io/spectra.py
index 5d3a5ef..62123a3 100644
--- a/python/valis/io/spectra.py
+++ b/python/valis/io/spectra.py
@@ -113,7 +113,7 @@ def extract_data(product: str, filepath: str, multispec: Union[int, str] = None)
         for key, val in data.items():
             if key == 'header':
                 continue
-            val.dtype = val.dtype.newbyteorder('=')
+            data[key] = val.byteswap().newbyteorder('=')
 
         return data