diff --git a/setup/extensions.json b/setup/extensions.json
index f92643e3a9..7824c01a9b 100644
--- a/setup/extensions.json
+++ b/setup/extensions.json
@@ -19,7 +19,7 @@
     {
         "name": "ffmpeg",
         "sources": "calibre/utils/ffmpeg.c",
-		"libraries": "avcodec avutil swresample",
+		"libraries": "swresample avcodec avutil",
         "inc_dirs": "!ffmpeg_inc_dirs",
         "lib_dirs": "!ffmpeg_lib_dirs",
 		"needs_c": "99"
diff --git a/src/calibre/gui2/tts/piper.py b/src/calibre/gui2/tts/piper.py
index 268e9fdfbc..46b355d73b 100644
--- a/src/calibre/gui2/tts/piper.py
+++ b/src/calibre/gui2/tts/piper.py
@@ -591,6 +591,9 @@ class PiperEmbedded:
         self.ensure_process_started()
         piper_done, errors_from_piper = [], []
         last_output_at = monotonic()
+        needs_conversion = sample_rate != self._current_audio_rate
+        if needs_conversion:
+            from calibre_extensions.ffmpeg import resample_raw_audio_16bit
 
         def callback(ok, payload):
             nonlocal last_output_at
@@ -623,10 +626,8 @@ class PiperEmbedded:
                         buf.append(data)
                     else:
                         stderr_data = detect_end_of_data(stderr_data + data, callback)
-            needs_conversion = sample_rate != self._current_audio_rate
             raw_data = b''.join(buf)
             if needs_conversion:
-                from calibre_extensions.ffmpeg import resample_raw_audio_16bit
                 raw_data = resample_raw_audio_16bit(raw_data, self._current_audio_rate, sample_rate)
             yield raw_data