fix: remove coarse seeking mode

Remove format-specific seeking optimizations in favor of always using
accurate mode. While coarse seeking was potentially faster for CBR
MP3s, it could lead to inaccurate position reporting since the player
cannot reliably determine the actual playback position after seeking.

CHANGELOG.md

@@ -10,6 +10,7 @@ and [Conventional Commits](https://www.conventionalcommits.org/en/v1.0.0/).
 ### Changed
 - [codec] Split `frame_duration` into `max_frame_length` and `max_frame_duration`
 - [decoder] Better error handling following Symphonia's recommendations
+- [decoder] Always use accurate seeking mode for reliable position reporting
 - [decoder] Fix logical error in `size_hint()` lower bound calculation
 - [decoder] Remove `ExactSizeIterator` implementation as total samples can't be determined exactly
 

src/decoder.rs

@@ -39,7 +39,7 @@ use symphonia::{
         codecs::{CodecParameters, CodecRegistry, DecoderOptions},
         errors::Error as SymphoniaError,
         formats::{FormatOptions, FormatReader, SeekMode, SeekTo},
-        io::{MediaSource, MediaSourceStream, MediaSourceStreamOptions},
+        io::{MediaSourceStream, MediaSourceStreamOptions},
         meta::{MetadataOptions, StandardTagKey, Value},
         probe::{Hint, Probe},
     },
@@ -105,9 +105,6 @@ pub struct Decoder {
     /// Codec decoder for converting encoded packets to PCM samples
     decoder: Box<dyn symphonia::core::codecs::Decoder>,
 
-    /// Seeking strategy (Coarse for CBR, Accurate for VBR)
-    seek_mode: SeekMode,
-
     /// Reusable sample buffer to minimize allocations
     buffer: Option<SampleBuffer<SampleFormat>>,
 
@@ -206,14 +203,6 @@ impl Decoder {
             )
         };
 
-        // Coarse seeking without a known byte length causes a panic.
-        // Further, it's not reliable for VBR streams.
-        let seek_mode = if track.is_cbr() && stream.byte_len().is_some() {
-            SeekMode::Coarse
-        } else {
-            SeekMode::Accurate
-        };
-
         let demuxer = probe
             .format(
                 &hint,
@@ -246,7 +235,6 @@ impl Decoder {
         Ok(Self {
             demuxer,
             decoder,
-            seek_mode,
 
             buffer: None,
             position: 0,
@@ -557,10 +545,7 @@ impl rodio::Source for Decoder {
 
     /// Attempts to seek to the specified position in the audio stream.
     ///
-    /// Uses Symphonia's seeking capabilities with format-specific optimizations:
-    /// * Coarse seeking for CBR content (faster)
-    /// * Accurate seeking for VBR content (more precise)
-    ///
+    /// Uses Symphonia's seeking capabilities to find the exact position in the stream.
     /// Also resets the decoder state to prevent audio glitches that could occur
     /// from seeking to a position that requires different decoding parameters.
     ///
@@ -573,7 +558,7 @@ impl rodio::Source for Decoder {
     fn try_seek(&mut self, pos: Duration) -> std::result::Result<(), SeekError> {
         self.demuxer
             .seek(
-                self.seek_mode,
+                SeekMode::Accurate,
                 SeekTo::Time {
                     track_id: None, // implies the default or first track
                     time: pos.into(),