Fix buffer bug in native audio.

Setting this buffer to 2400 was only enough to store 50m of sound
at 48,000 samples/sec. I've also done a small refactor here to
make this buffer scale with sample rate.

gui/src/imp/native_audio.rs

@@ -22,6 +22,8 @@ pub struct AudioSystem {
 
 const SAMPLE_RATE: u32 = 48_000;
 const PACKET_SAMPLES: u32 = 960;
+// Divide by 1000 to get samples per ms, then multiply by 60ms for max Opus frame size.
+const MAX_DECODE_SAMPLES: usize = SAMPLE_RATE as usize / 1000 * 60;
 
 fn encode_and_send(
     state: TransmitState,
@@ -184,7 +186,7 @@ impl AudioSystem {
             decoder,
             stream,
             buffer,
-            tmp: vec![0; 2400],
+            tmp: vec![0; MAX_DECODE_SAMPLES],
         })
     }
 }
@@ -198,14 +200,12 @@ pub struct AudioPlayer {
 
 impl AudioPlayer {
     pub fn play_opus(&mut self, payload: &[u8]) {
-        let len = loop {
-            match self.decoder.decode(payload, &mut self.tmp, false) {
-                Ok(l) => break l,
+        let len = match self.decoder.decode(payload, &mut self.tmp, false) {
+            Ok(l) => l,
             Err(e) => {
                 error!("opus decode error {e:?}");
                 return;
             }
-            }
         };
 
         let mut buffer = self.buffer.lock().unwrap();