diff --git a/nestsClient/src/jvmAndroid/kotlin/com/vitorpamplona/nestsclient/transport/QuicWebTransportFactory.kt b/nestsClient/src/jvmAndroid/kotlin/com/vitorpamplona/nestsclient/transport/QuicWebTransportFactory.kt
index a86563fc2..4958821bf 100644
--- a/nestsClient/src/jvmAndroid/kotlin/com/vitorpamplona/nestsclient/transport/QuicWebTransportFactory.kt
+++ b/nestsClient/src/jvmAndroid/kotlin/com/vitorpamplona/nestsclient/transport/QuicWebTransportFactory.kt
@@ -20,6 +20,7 @@
  */
 package com.vitorpamplona.nestsclient.transport
 
+import com.vitorpamplona.quartz.utils.Log
 import com.vitorpamplona.quic.connection.QuicConnection
 import com.vitorpamplona.quic.connection.QuicConnectionConfig
 import com.vitorpamplona.quic.connection.QuicConnectionDriver
@@ -37,9 +38,12 @@ import com.vitorpamplona.quic.webtransport.buildExtendedConnectHeaders
 import com.vitorpamplona.quic.webtransport.encodeHeadersFrame
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
 import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.flow
+import kotlinx.coroutines.launch
 
 /**
  * Pure-Kotlin WebTransport over QUIC v1, sitting on top of every layer in
@@ -181,7 +185,7 @@ class QuicWebTransportFactory(
             }
 
             val state = QuicWebTransportSessionState(conn, driver, requestStream.streamId)
-            return QuicWebTransportSession(state)
+            return QuicWebTransportSession(state, parentScope)
         } catch (we: WebTransportException) {
             throw we
         } catch (ce: kotlinx.coroutines.CancellationException) {
@@ -259,9 +263,43 @@ class QuicWebTransportFactory(
 /** Adapter that wraps the :quic [QuicWebTransportSessionState] in the nestsClient interface. */
 class QuicWebTransportSession(
     private val state: QuicWebTransportSessionState,
+    parentScope: CoroutineScope? = null,
 ) : WebTransportSession {
     override val isOpen: Boolean get() = state.isOpen
 
+    /**
+     * Periodic flow-control snapshot logger. Wakes every
+     * [SNAPSHOT_INTERVAL_MS] and dumps the QUIC layer's view of cap +
+     * count + send credit so we can correlate "audio cliff at uni
+     * stream #N" against "what did flow control look like at that
+     * moment". Cancelled when [close] tears down the session.
+     *
+     * Lazy-launched (via [parentScope]) only when the caller has
+     * provided a scope to host it — tests construct the session
+     * without one and don't need the logger.
+     */
+    private val snapshotJob: Job? =
+        parentScope?.launch {
+            while (true) {
+                delay(SNAPSHOT_INTERVAL_MS)
+                if (!state.isOpen) break
+                runCatching {
+                    val snap = state.connection.flowControlSnapshot()
+                    Log.d("NestQuic") {
+                        "snapshot peerInitiatedUni=${snap.peerInitiatedUniCount} " +
+                            "advertisedMaxStreamsUni=${snap.advertisedMaxStreamsUni} " +
+                            "peerInitMaxStreamsUni=${snap.peerInitialMaxStreamsUni} " +
+                            "sendCredit=${snap.sendConnectionFlowCredit} " +
+                            "consumed=${snap.sendConnectionFlowConsumed} " +
+                            "pendingBytes=${snap.totalEnqueuedNotSentBytes} " +
+                            "pendingStreams=${snap.streamsWithPendingBytes}/${snap.totalStreamsTracked} " +
+                            "udpRecvDatagrams=${snap.udp?.receivedDatagrams ?: -1L} " +
+                            "udpRecvBytes=${snap.udp?.receivedBytes ?: -1L}"
+                    }
+                }
+            }
+        }
+
     /**
      * Diagnostic-only passthrough to
      * [com.vitorpamplona.quic.connection.QuicConnection.flowControlSnapshot].
@@ -326,8 +364,19 @@ class QuicWebTransportSession(
         code: Int,
         reason: String,
     ) {
+        snapshotJob?.cancel()
         state.close(code, reason)
     }
+
+    private companion object {
+        /**
+         * Cadence for the periodic flow-control snapshot. 5 s is short
+         * enough to catch the audio-cliff transition (which lands within
+         * 5–15 s of subscribe) and long enough that the snapshot itself
+         * isn't a meaningful CPU cost.
+         */
+        const val SNAPSHOT_INTERVAL_MS = 5_000L
+    }
 }
 
 private class QuicBidiStreamAdapter(