diff --git a/api/views.py b/api/views.py
index 81823a0..ec9a7a4 100755
--- a/api/views.py
+++ b/api/views.py
@@ -3,7 +3,7 @@ import os
 
 from django.core.exceptions import PermissionDenied, ObjectDoesNotExist
 from django.core.files.base import ContentFile
-from django.core.files.storage import FileSystemStorage, default_storage
+from django.core.files.storage import FileSystemStorage
 from django.db.models import Count
 from django.http.response import HttpResponse
 from rest_framework import viewsets
@@ -17,9 +17,8 @@ from rest_framework.status import HTTP_202_ACCEPTED, HTTP_401_UNAUTHORIZED, HTTP
     HTTP_200_OK, HTTP_204_NO_CONTENT
 
 from api import serializers
-from core.utils import cdn
 from dss import settings
-from spa.tasks import create_waveform_task, upload_to_cdn_task
+from spa import tasks
 from spa.models.genre import Genre
 from spa.models.activity import ActivityPlay
 from spa.models.mix import Mix
@@ -187,13 +186,13 @@ class PartialMixUploadView(views.APIView):
                 logger.debug("Processing input_file: {0}".format(input_file))
                 logger.debug("Connecting to broker: {0}".format(settings.BROKER_URL))
 
-                from celery import group
-                (create_waveform_task.s(input_file, uid) |
-                 group(
-                     upload_to_cdn_task.s(filetype='mp3', uid=uid, container_name='mixes'),
-                     upload_to_cdn_task.s(filetype='png', uid=uid, container_name='waveforms')
-                 )
-                 ).delay()
+                from celery import group, chain
+                (
+                    tasks.create_waveform_task.s(input_file, uid) |
+                    tasks.upload_to_cdn_task.subtask(('mp3', uid, 'mixes'), immutable=True) |
+                    tasks.upload_to_cdn_task.subtask(('png', uid, 'waveforms'), immutable=True) |
+                    tasks.notify_subscriber.subtask((request.user.userprofile.get_session_id(), uid), immutable=True)
+                ).delay()
                 logger.debug("Waveform task started")
 
             except Exception, ex:
diff --git a/spa/signals.py b/spa/signals.py
index cb131ba..1390a55 100755
--- a/spa/signals.py
+++ b/spa/signals.py
@@ -4,6 +4,7 @@ from django.db.models.signals import post_save, pre_save, m2m_changed
 from django.dispatch import Signal, receiver
 
 from django.contrib.auth.models import User
+from core.realtime import activity
 
 from core.utils.audio.mp3 import mp3_length
 from spa.models.activity import ActivityFollow
diff --git a/spa/tasks.py b/spa/tasks.py
index c921c5a..10dbd05 100755
--- a/spa/tasks.py
+++ b/spa/tasks.py
@@ -1,6 +1,7 @@
 from celery.task import task
 import os
 import logging
+from core.realtime import activity
 
 from core.utils import cdn
 from spa.signals import waveform_generated_signal
@@ -30,7 +31,7 @@ def create_waveform_task(in_file, uid):
 
 
 @task(timse_limit=3600)
-def upload_to_cdn_task(in_file, filetype, uid, container_name):
+def upload_to_cdn_task(filetype, uid, container_name):
     source_file = os.path.join(settings.CACHE_ROOT, '{0}/{1}.{2}'.format(container_name, uid, filetype))
     logger.info("Sending {0} to azure".format(uid))
     try:
@@ -53,3 +54,9 @@ def update_geo_info_task(ip_address, profile_id):
     except Exception, e:
         logger.exception(e)
         pass
+
+
+@task
+def notify_subscriber(session_id, uid):
+    if session_id is not None:
+        activity.post_activity('user:message', session_id, {'type': 'waveform', 'target': uid})