diff --git a/audio/src/fetch.rs b/audio/src/fetch.rs
index 46d8a88a..a791841c 100644
--- a/audio/src/fetch.rs
+++ b/audio/src/fetch.rs
@@ -541,7 +541,7 @@ impl Future for AudioFileFetchDataReceiver {
                             if 0.001 * (duration.as_millis() as f64) > MAXIMUM_ASSUMED_PING_TIME_SECONDS {
                                 duration_ms = (MAXIMUM_ASSUMED_PING_TIME_SECONDS * 1000.0) as u64;
                             } else {
-                                duration_ms = duration.as_secs() * 1000 + duration.subsec_millis() as u64;
+                                duration_ms = duration.as_millis() as u64;
                             }
                             let _ = self.file_data_tx.unbounded_send(ReceivedData::ResponseTimeMs(duration_ms as usize));
                             self.measure_ping_time = false;
@@ -896,15 +896,16 @@ impl Future for AudioFileFetch {
                 download_status.requested.minus(&download_status.downloaded).len()
             };
 
-            let ping_time_seconds = 0.0001 * self.shared.ping_time_ms.load(atomic::Ordering::Relaxed) as f64;
+            let ping_time_seconds = 0.001 * self.shared.ping_time_ms.load(atomic::Ordering::Relaxed) as f64;
+            let download_rate = self.session.channel().get_download_rate_estimate();
 
             let desired_pending_bytes = max(
                 (PREFETCH_THRESHOLD_FACTOR * ping_time_seconds * self.shared.stream_data_rate as f64) as usize,
-                (FAST_PREFETCH_THRESHOLD_FACTOR * ping_time_seconds * self.session.channel().get_download_rate_estimate() as f64) as usize
+                (FAST_PREFETCH_THRESHOLD_FACTOR * ping_time_seconds * download_rate as f64) as usize
             );
 
             if bytes_pending < desired_pending_bytes {
-                trace!("Prefetching more data. pending bytes({}) < {}",bytes_pending, desired_pending_bytes);
+                trace!("Prefetching more data. pending: {}, desired: {}, ping: {}, rate: {}", bytes_pending, desired_pending_bytes, ping_time_seconds, download_rate);
                 self.pre_fetch_more_data(desired_pending_bytes - bytes_pending);
             }
         }
diff --git a/audio/src/range_set.rs b/audio/src/range_set.rs
index 12b82997..835477be 100644
--- a/audio/src/range_set.rs
+++ b/audio/src/range_set.rs
@@ -186,6 +186,7 @@ impl RangeSet {
                 }
 
                 if index < self.ranges.len() && self.ranges[index].start < range.end() {
+                    self.ranges[index].length -= range.end() - self.ranges[index].start;
                     self.ranges[index].start = range.end();
                 }
 
@@ -199,6 +200,7 @@ impl RangeSet {
                     length: range.start - self.ranges[index].start,
                 };
 
+                self.ranges[index].length -= range.end() - self.ranges[index].start;
                 self.ranges[index].start = range.end();
 
                 self.ranges.insert(index, first_range);
diff --git a/core/src/channel.rs b/core/src/channel.rs
index 62620e36..9471c07a 100644
--- a/core/src/channel.rs
+++ b/core/src/channel.rs
@@ -14,7 +14,6 @@ component! {
         download_rate_estimate: usize = 0,
         download_measurement_start: Option<Instant> = None,
         download_measurement_bytes: usize = 0,
-        download_measurement_last_received: Option<Instant> = None,
     }
 }
 
@@ -72,23 +71,15 @@ impl ChannelManager {
 
             let current_time = Instant::now();
             if let Some(download_measurement_start) = inner.download_measurement_start {
-                if let Some(download_measurement_last_received) = inner.download_measurement_last_received {
-                    if (current_time - download_measurement_start).as_millis() > 1000 {
-                        if (current_time - download_measurement_last_received).as_millis() <= 500 {
-                            inner.download_rate_estimate = 1000 * inner.download_measurement_bytes / (current_time - download_measurement_start).as_millis() as usize;
-                        } else {
-                            inner.download_rate_estimate = 1000 * inner.download_measurement_bytes / (500+(download_measurement_last_received - download_measurement_start).as_millis() as usize);
-                        }
-
-                        inner.download_measurement_start = Some(current_time);
-                        inner.download_measurement_bytes = 0;
-                    }
+                if (current_time - download_measurement_start).as_millis() > 1000 {
+                    inner.download_rate_estimate = 1000 * inner.download_measurement_bytes / (current_time - download_measurement_start).as_millis() as usize;
+                    inner.download_measurement_start = Some(current_time);
+                    inner.download_measurement_bytes = 0;
                 }
             } else {
                 inner.download_measurement_start = Some(current_time);
             }
 
-            inner.download_measurement_last_received = Some(current_time);
             inner.download_measurement_bytes += data.len();
 
             if let Entry::Occupied(entry) = inner.channels.entry(id) {