Live View page subsamples at low event rate

[QCaudron]

On the Live View page, with no filters, when I click "Subscribe new events", I'm able to see each event when I create events every three seconds :

while True:
    response = requests.post(url, data=json.dumps(
         {"api": {"api_key":"WRITE_KEY"},
          "collection": np.random.choice(events),
          "properties": {"_time": str(datetime.today()),
                         "_user": np.random.choice(users)}}))
     print(response.text)
     sleep(3)

When I change this to a two-second delay between events, the Live View page starts choking, only showing one in about every three events.

Any faster than that, and no events show up at all.