Handle ALSA devices when PortAudio reports no matching output

sendspin/audio_devices.py

@@ -13,6 +13,8 @@
 
 logger = logging.getLogger(__name__)
 
+_PORTAUDIO_NO_OUTPUT_DEVICE_MATCHING = "No output device matching"
+
 SOUNDDEVICE_DTYPE_MAP: dict[int, str] = {
     16: "int16",
     24: "int24",
@@ -268,6 +270,11 @@ def list_alsa_devices() -> list[tuple[str, str]]:
     return devices
 
 
+def _alsa_device_exists(name: str) -> bool:
+    """Return True if ALSA lists *name* as a PCM device."""
+    return any(dev_name == name for dev_name, _ in list_alsa_devices())
+
+
 def resolve_audio_device(device_arg: str | None) -> AudioDevice:
     """Resolve audio device from a CLI argument.
 
@@ -319,13 +326,20 @@ def _try_alsa_device(name: str) -> AudioDevice | None:
     """
     try:
         sounddevice.check_output_settings(device=name)
-    except sounddevice.PortAudioError:
-        return None
+    except sounddevice.PortAudioError as err:
+        # sounddevice exposes this PortAudio lookup failure only in the
+        # error message, without a stable code to distinguish it from
+        # actual device-open failures.
+        # Validate it exists in ALSA before accepting it with safe defaults.
+        err_msg = str(err.args[0]) if err.args else ""
+        if _PORTAUDIO_NO_OUTPUT_DEVICE_MATCHING not in err_msg:
+            return None
+        if not _alsa_device_exists(name):
+            return None
     except ValueError:
         # PortAudio doesn't recognize this device name (e.g. hw:CARD=...,DEV=...).
         # Validate it exists in ALSA before accepting it with safe defaults.
-        alsa_names = {dev_name for dev_name, _ in list_alsa_devices()}
-        if name not in alsa_names:
+        if not _alsa_device_exists(name):
             return None
 
     # Try to query device info from PortAudio

tests/test_audio_devices.py

@@ -68,6 +68,39 @@ def test_try_alsa_device_accepts_hw_card_format_known_to_alsa():
     assert result.sample_rate == 48000.0
 
 
+def test_try_alsa_device_accepts_hw_card_format_when_portaudio_reports_no_match():
+    """hw:CARD=...,DEV=... should work when ALSA lists it but PortAudio can't match it."""
+    alsa_list = [
+        (
+            "hw:CARD=sndrpihifiberry,DEV=0",
+            "snd_rpi_hifiberry_dacplus, HiFiBerry DAC+ HiFi",
+        ),
+    ]
+    with (
+        patch.object(
+            sounddevice,
+            "check_output_settings",
+            side_effect=sounddevice.PortAudioError(
+                f"{_mod._PORTAUDIO_NO_OUTPUT_DEVICE_MATCHING} 'hw:CARD=sndrpihifiberry,DEV=0'",
+                -1,
+                "",
+            ),
+        ),
+        patch.object(
+            sounddevice,
+            "query_devices",
+            side_effect=ValueError("not found"),
+        ),
+        patch.object(_mod, "list_alsa_devices", return_value=alsa_list),
+    ):
+        result = _try_alsa_device("hw:CARD=sndrpihifiberry,DEV=0")
+
+    assert result is not None
+    assert result.alsa_device_name == "hw:CARD=sndrpihifiberry,DEV=0"
+    assert result.output_channels == 2
+    assert result.sample_rate == 48000.0
+
+
 def test_try_alsa_device_returns_none_for_unknown_hw_card():
     """hw:CARD=...,DEV=... not in ALSA list should return None."""
     with (