diff --git a/ext/ogg/gstoggstream.c b/ext/ogg/gstoggstream.c
index 50a132f3f9..2889b89f49 100644
--- a/ext/ogg/gstoggstream.c
+++ b/ext/ogg/gstoggstream.c
@@ -637,6 +637,31 @@ packet_duration_flac (GstOggStream * pad, ogg_packet * packet)
   if (block_size_index >= 8) {
     return 256 << (block_size_index - 8);
   }
+  if (block_size_index == 6 || block_size_index == 7) {
+    guint len, bytes = (block_size_index - 6) + 1;
+    guint8 tmp;
+
+    if (packet->bytes < 4 + 1 + bytes)
+      return -1;
+    tmp = packet->packet[4];
+    /* utf-8 prefix */
+    len = 0;
+    while (tmp & 0x80) {
+      len++;
+      tmp <<= 1;
+    }
+    if (len == 2)
+      return -1;
+    if (len == 0)
+      len++;
+    if (packet->bytes < 4 + len + bytes)
+      return -1;
+    if (bytes == 1) {
+      return packet->packet[4 + len] + 1;
+    } else {
+      return GST_READ_UINT16_BE (packet->packet + 4 + len) + 1;
+    }
+  }
   return -1;
 }
 
@@ -1156,7 +1181,7 @@ static const GstOggMap mappers[] = {
     NULL
   },
   {
-    "\177FLAC", 4, 36,
+    "\177FLAC", 5, 36,
     "audio/x-flac",
     setup_flac_mapper,
     granulepos_to_granule_default,
diff --git a/ext/pango/gsttextoverlay.c b/ext/pango/gsttextoverlay.c
index cb5f55946c..3e4a0ee7f1 100644
--- a/ext/pango/gsttextoverlay.c
+++ b/ext/pango/gsttextoverlay.c
@@ -2035,7 +2035,8 @@ gst_text_overlay_video_chain (GstPad * pad, GstBuffer * buffer)
     gint fps_num, fps_denom;
 
     s = gst_caps_get_structure (GST_PAD_CAPS (pad), 0);
-    if (gst_structure_get_fraction (s, "framerate", &fps_num, &fps_denom)) {
+    if (gst_structure_get_fraction (s, "framerate", &fps_num, &fps_denom) &&
+        fps_num && fps_denom) {
       GST_DEBUG_OBJECT (overlay, "estimating duration based on framerate");
       stop = start + gst_util_uint64_scale_int (GST_SECOND, fps_denom, fps_num);
     } else {
diff --git a/gst-libs/gst/rtp/gstbasertpaudiopayload.c b/gst-libs/gst/rtp/gstbasertpaudiopayload.c
index 966d93d74b..1daa783d66 100644
--- a/gst-libs/gst/rtp/gstbasertpaudiopayload.c
+++ b/gst-libs/gst/rtp/gstbasertpaudiopayload.c
@@ -98,6 +98,7 @@ struct _GstBaseRTPAudioPayloadPrivate
   guint cached_mtu;
   guint cached_min_ptime;
   guint cached_max_ptime;
+  guint cached_ptime;
   guint cached_min_length;
   guint cached_max_length;
 };
@@ -516,6 +517,7 @@ gst_base_rtp_audio_payload_get_lengths (GstBaseRTPPayload *
 
   /* check cached values */
   if (G_LIKELY (priv->cached_mtu == mtu
+          && priv->cached_ptime == basepayload->abidata.ABI.ptime
           && priv->cached_max_ptime == basepayload->max_ptime
           && priv->cached_min_ptime == basepayload->min_ptime)) {
     /* if nothing changed, return cached values */
@@ -546,8 +548,21 @@ gst_base_rtp_audio_payload_get_lengths (GstBaseRTPPayload *
   if (*min_payload_len > *max_payload_len)
     *min_payload_len = *max_payload_len;
 
+  /* If the ptime is specified in the caps, tried to adhere to it exactly */
+  if (basepayload->abidata.ABI.ptime) {
+    guint ptime_in_bytes = priv->time_to_bytes (payload,
+        basepayload->abidata.ABI.ptime);
+
+    /* clip to computed min and max lengths */
+    ptime_in_bytes = MAX (*min_payload_len, ptime_in_bytes);
+    ptime_in_bytes = MIN (*max_payload_len, ptime_in_bytes);
+
+    *min_payload_len = *max_payload_len = ptime_in_bytes;
+  }
+
   /* cache values */
   priv->cached_mtu = mtu;
+  priv->cached_ptime = basepayload->abidata.ABI.ptime;
   priv->cached_min_ptime = basepayload->min_ptime;
   priv->cached_max_ptime = basepayload->max_ptime;
   priv->cached_min_length = *min_payload_len;
diff --git a/gst-libs/gst/rtp/gstbasertppayload.c b/gst-libs/gst/rtp/gstbasertppayload.c
index e3b4d7f8ab..a6d8eb3ce4 100644
--- a/gst-libs/gst/rtp/gstbasertppayload.c
+++ b/gst-libs/gst/rtp/gstbasertppayload.c
@@ -46,6 +46,9 @@ struct _GstBaseRTPPayloadPrivate
   gboolean ssrc_random;
   guint16 next_seqnum;
   gboolean perfect_rtptime;
+
+  gint64 prop_max_ptime;
+  gint64 caps_max_ptime;
 };
 
 /* BaseRTPPayload signals and args */
@@ -281,6 +284,9 @@ gst_basertppayload_init (GstBaseRTPPayload * basertppayload, gpointer g_class)
   basertppayload->encoding_name = NULL;
 
   basertppayload->clock_rate = 0;
+
+  basertppayload->priv->caps_max_ptime = DEFAULT_MAX_PTIME;
+  basertppayload->priv->prop_max_ptime = DEFAULT_MAX_PTIME;
 }
 
 static void
@@ -469,6 +475,21 @@ copy_fixed (GQuark field_id, const GValue * value, GstStructure * dest)
   return TRUE;
 }
 
+static void
+update_max_ptime (GstBaseRTPPayload * basertppayload)
+{
+  if (basertppayload->priv->caps_max_ptime != -1 &&
+      basertppayload->priv->prop_max_ptime != -1)
+    basertppayload->max_ptime = MIN (basertppayload->priv->caps_max_ptime,
+        basertppayload->priv->prop_max_ptime);
+  else if (basertppayload->priv->caps_max_ptime != -1)
+    basertppayload->max_ptime = basertppayload->priv->caps_max_ptime;
+  else if (basertppayload->priv->prop_max_ptime != -1)
+    basertppayload->max_ptime = basertppayload->priv->prop_max_ptime;
+  else
+    basertppayload->max_ptime = DEFAULT_MAX_PTIME;
+}
+
 /**
  * gst_basertppayload_set_outcaps:
  * @payload: a #GstBaseRTPPayload
@@ -508,6 +529,9 @@ gst_basertppayload_set_outcaps (GstBaseRTPPayload * payload, gchar * fieldname,
     GST_DEBUG_OBJECT (payload, "custom added: %" GST_PTR_FORMAT, srccaps);
   }
 
+  payload->priv->caps_max_ptime = DEFAULT_MAX_PTIME;
+  payload->abidata.ABI.ptime = 0;
+
   /* the peer caps can override some of the defaults */
   peercaps = gst_pad_peer_get_caps (payload->srcpad);
   if (peercaps == NULL) {
@@ -524,6 +548,7 @@ gst_basertppayload_set_outcaps (GstBaseRTPPayload * payload, gchar * fieldname,
     GstStructure *s, *d;
     const GValue *value;
     gint pt;
+    gint max_ptime, ptime;
 
     /* peer provides caps we can use to fixate, intersect. This always returns a
      * writable caps. */
@@ -537,6 +562,12 @@ gst_basertppayload_set_outcaps (GstBaseRTPPayload * payload, gchar * fieldname,
     /* get first structure */
     s = gst_caps_get_structure (temp, 0);
 
+    if (gst_structure_get_int (s, "maxptime", &max_ptime) && max_ptime > 0)
+      payload->priv->caps_max_ptime = max_ptime * GST_MSECOND;
+
+    if (gst_structure_get_int (s, "ptime", &ptime) && ptime > 0)
+      payload->abidata.ABI.ptime = ptime;
+
     if (gst_structure_get_int (s, "payload", &pt)) {
       /* use peer pt */
       GST_BASE_RTP_PAYLOAD_PT (payload) = pt;
@@ -602,6 +633,8 @@ gst_basertppayload_set_outcaps (GstBaseRTPPayload * payload, gchar * fieldname,
     GST_DEBUG_OBJECT (payload, "with peer caps: %" GST_PTR_FORMAT, srccaps);
   }
 
+  update_max_ptime (payload);
+
   res = gst_pad_set_caps (GST_BASE_RTP_PAYLOAD_SRCPAD (payload), srccaps);
   gst_caps_unref (srccaps);
 
@@ -858,7 +891,8 @@ gst_basertppayload_set_property (GObject * object, guint prop_id,
           basertppayload->seqnum_offset, priv->seqnum_offset_random);
       break;
     case PROP_MAX_PTIME:
-      basertppayload->max_ptime = g_value_get_int64 (value);
+      basertppayload->priv->prop_max_ptime = g_value_get_int64 (value);
+      update_max_ptime (basertppayload);
       break;
     case PROP_MIN_PTIME:
       basertppayload->min_ptime = g_value_get_int64 (value);
diff --git a/gst-libs/gst/rtp/gstbasertppayload.h b/gst-libs/gst/rtp/gstbasertppayload.h
index e57f74ea97..1591c104e1 100644
--- a/gst-libs/gst/rtp/gstbasertppayload.h
+++ b/gst-libs/gst/rtp/gstbasertppayload.h
@@ -111,7 +111,12 @@ struct _GstBaseRTPPayload
   /*< private >*/
   GstBaseRTPPayloadPrivate *priv;
 
-  gpointer _gst_reserved[GST_PADDING - (sizeof(guint64)/sizeof(gpointer)) - 1];
+  union  {
+    struct {
+      guint ptime; /* in ms */
+    } ABI;
+    gpointer _gst_reserved[GST_PADDING - (sizeof(guint64)/sizeof(gpointer)) - 1];
+  } abidata;
 };
 
 struct _GstBaseRTPPayloadClass