diff --git a/agent/component.c b/agent/component.c
index f369bf8997f7e3612e478affc4e6c16ea502e78b..a5c90960085ffab85a56a878bb42b37f803cfaa8 100644
--- a/agent/component.c
+++ b/agent/component.c
@@ -855,6 +855,8 @@ typedef struct {
   guint stream_id;
   guint component_id;
   guint component_socket_sources_age;
+
+  GIOCondition condition;
 } ComponentSource;
 
 static gboolean
@@ -984,6 +986,7 @@ static GSourceFuncs component_source_funcs = {
  * @component_id: The component's number
  * @pollable_stream: a #GPollableInputStream or #GPollableOutputStream to pass
  * to dispatched callbacks
+ * @condition: underlying socket condition to dispatch on
  * @cancellable: (allow-none): a #GCancellable, or %NULL
  *
  * Create a new #ComponentSource, a type of #GSource which proxies poll events
@@ -1000,13 +1003,15 @@ static GSourceFuncs component_source_funcs = {
  * Returns: (transfer full): a new #ComponentSource; unref with g_source_unref()
  */
 GSource *
-component_input_source_new (NiceAgent *agent, guint stream_id,
-    guint component_id, GPollableInputStream *pollable_istream,
+component_source_new (NiceAgent *agent, guint stream_id,
+    guint component_id, GObject *pollable_stream,
+    GIOCondition condition,
     GCancellable *cancellable)
 {
   ComponentSource *component_source;
 
-  g_assert (G_IS_POLLABLE_INPUT_STREAM (pollable_istream));
+  g_assert (G_IS_POLLABLE_INPUT_STREAM (pollable_stream) ||
+            G_IS_POLLABLE_OUTPUT_STREAM (pollable_stream));
 
   component_source =
       (ComponentSource *)
@@ -1014,7 +1019,7 @@ component_input_source_new (NiceAgent *agent, guint stream_id,
   g_source_set_name ((GSource *) component_source, "ComponentSource");
 
   component_source->component_socket_sources_age = 0;
-  component_source->pollable_stream = g_object_ref (pollable_istream);
+  component_source->pollable_stream = g_object_ref (pollable_stream);
   g_weak_ref_init (&component_source->agent_ref, agent);
   component_source->stream_id = stream_id;
   component_source->component_id = component_id;
diff --git a/agent/component.h b/agent/component.h
index 143c212e22ea1e579c9c399ce4c977a4e8546a66..0c28d2e3053449352ddb304fcbf74ff66e80f085 100644
--- a/agent/component.h
+++ b/agent/component.h
@@ -237,9 +237,9 @@ void
 component_free_socket_sources (Component *component);
 
 GSource *
-component_input_source_new (NiceAgent *agent, guint stream_id,
-    guint component_id, GPollableInputStream *pollable_istream,
-    GCancellable *cancellable);
+component_source_new (NiceAgent *agent, guint stream_id,
+    guint component_id, GObject *pollable_istream,
+    GIOCondition condition, GCancellable *cancellable);
 
 GMainContext *
 component_dup_io_context (Component *component);
diff --git a/agent/inputstream.c b/agent/inputstream.c
index a6a678bfa644ace384c82b4adaf13beeae1d1908..5da3908bd1582216f1efc6eaa9cb9d4c345714ac 100644
--- a/agent/inputstream.c
+++ b/agent/inputstream.c
@@ -424,8 +424,8 @@ nice_input_stream_create_source (GPollableInputStream *stream,
   if (agent == NULL)
     goto dummy_source;
 
-  component_source = component_input_source_new (agent, priv->stream_id,
-      priv->component_id, stream, cancellable);
+  component_source = component_source_new (agent, priv->stream_id,
+      priv->component_id, G_OBJECT (stream), G_IO_IN, cancellable);
 
   g_object_unref (agent);
 
diff --git a/agent/outputstream.c b/agent/outputstream.c
index bf34c86bf7d53c7a23e3dc90104de12e3a70827d..cd0d493d2f192452e5cf341d00980d8f07337d5c 100644
--- a/agent/outputstream.c
+++ b/agent/outputstream.c
@@ -618,6 +618,15 @@ nice_output_stream_create_source (GPollableOutputStream *stream,
     g_source_set_dummy_callback (cancellable_source);
     g_source_add_child_source (component_source, cancellable_source);
     g_source_unref (cancellable_source);
+  } else if (!agent->reliable) {
+    /* UDP streams are almost always writeable. */
+    GSource *child_source;
+
+    child_source = component_source_new (agent, priv->stream_id,
+      priv->component_id, G_OBJECT (stream), G_IO_OUT, cancellable);
+    g_source_set_dummy_callback (child_source);
+    g_source_add_child_source (component_source, child_source);
+    g_source_unref (child_source);
   }
 
 done: