diff --git a/source/nvwave.py b/source/nvwave.py
index 438c3c4e5d5..168204e07d6 100644
--- a/source/nvwave.py
+++ b/source/nvwave.py
@@ -18,7 +18,8 @@
 	c_void_p,
 	CFUNCTYPE,
 	c_float,
-	string_at,
+	c_char_p,
+	cast,
 )
 from comtypes import HRESULT
 from comtypes.hresult import E_INVALIDARG
@@ -339,12 +340,13 @@ def feed(
 		# turn off trimming temporarily.
 		if self._purpose is AudioPurpose.SPEECH and self._isLeadingSilenceInserted:
 			self.startTrimmingLeadingSilence(False)
-		if not isinstance(data, bytes):
-			data = string_at(data, size)
+		# wasPlay_feed requires c_char_p, so cast data to c_char_p before calling.
+		# Casting bytes to c_char_p is also fine, as long as the original data is not released.
+		dataptr = cast(data, c_char_p)
 		try:
 			wasapi.wasPlay_feed(
 				self._player,
-				data,
+				dataptr,
 				size if size is not None else len(data),
 				byref(feedId) if onDone else None,
 			)