Overcoming the Demand 5 TV Catchup Performance Problem

Solving the Demand 5, Flash Movie problem - and other Catch Up TV website issues

If you are from the UK then you may often like to catch up on missed TV programmes by watching the online TV catch up services such as BBC iPlayer, Channel Four's 4OD and Channel 5's TV Catch Up service called Demand 5.

The past few nights I have been trying to catch up on a number of programmes shown on Channel 5 as for some reason Five Star has stopped showing the latest episode of Burn Notice on a Sunday afternoon and I like to watch other shows (when they are available) like NCIS and The Mentalist etc so I try to use Channel 5's catch up website Demand 5.

I really wish they would buy the rights to show for longer so that you could watch a programme for more than just 7 days but then it's not called catchup TV for nothing and most TV programmes are made in the USA.

However when I use the Demand 5 website to watch the programme I experience a very annoying problem which effects every browser and computer I tried using including Chrome, FireFox, Safari and IE 8 on a Sony Vaio Windows XP 32 bit Dual Core and IE 9 on a Dell Windows 7 64 bit Quad core.

The Demand 5 catchup TV problem means that pre-show adverts play fine and then after a period of anything between a few seconds and a couple of minutes of the actual show playing the Demand 5 Catchup TV programme would either just freeze up and not start playing again at all. 

Or it would play for a while before stopping for a few seconds as if it was buffering more content before playing for another few seconds again - totally unwatchable.

I couldn't even move the skip bar backwards or forward and the pause / play button just didn't work at all.

A refresh would reload the page, show the adverts before the programme again and then the problem would re-occur. It was all very annoying..

After a number of seemingly ignored comments to Demand 5 complaining about them not fixing the problem and after reading on almost every show on the site that a large number of other people have had similar problems I tried solving the issue myself.

If you go to any show on Demand 5 and read the comments at the bottom e.g www.channel5.com/shows/ you will see comments along the following lines.

"Really poor transmission of episode 23. Can't get more than 20 seconds of coherent dialogue and then it freezes"

"Impossible to watch because of the poor service from Demand Five's website. Even worse than Karen's experience."

"Why is demand 5 not working? It hasn't worked for several weeks. You don't get this with iplayer!!!"

"doesnt seem to be able to play anything"

"wow the longest i got to watch before it froze was 50sec. i did give up 5min in though. I'm with sue off to iplayer which works."

And those are just a snapshot of the many comments on a couple of shows I wanted to watch today all complaining about the Demand 5 website video freezing or not playing at all. 

Demand 5 really need to fix this problem if they want to keep visitors coming to the site.

Due to my own comments and complaints not being answered I tried fixing the problem with Demand Five freezing myself - only because I really wanted to watch the latest episode of NCIS.

I wasn't going to step through all their custom JavaScript and I have no idea what they are doing server side so proper debugging is out of the question but what you can do in situations like this is turn everything else off and then back on again one by one to see if any section of the browser or website is causing the problem.

So without knowing whether they are running some client side code constantly that rewrites the DOM such as many sites try to use to beat all the plugins that are designed to hide adverts, images and flash I could try to see if turning off those parts of the site helped as they maybe running code to constantly re-insert adverts into the HTML to replace any removed by plugins like AdBlocker.

If they were doing something like this (and I don't know if the are) then it's possible that a race condition might occur between Demand 5's own advertising code and any any plugins or virus checkers (which have built in anti-banner options) that constantly scan and rebuild the DOM.Only proper debugging will prove if that is happening,

Debgging the Demand 5 website Performance Problem

So to get a fix for the the Demand 5 problem as soon as possible the first thing I did were all the normal things that developers try when met with similar issues. If you find similar problems on other sites or with plugins for websites you should always try this list first to rule them out as reasons for the problem.

• Disabling all cookies - the Web Developer Toolbar in Firefox is great for this and if you are not signing into the website there is no need for cookies to be enabled anyway.
• Disabling Java - Most websites don't even use Java Applets any-more so its not really needed until you find a site that actually makes use of it.
• Disabling JavaScript - Most websites that show TV content actually require JavaScript to be enabled for their site to work at all even though a basic Flash OBJECT or VIDEO element on a page outputted with server side code playing a movie doesn't require it. However companies like Demand 5 or iPlayer don't do this because it mean their content can easily be stolen or watched overseas by non UK citizens etc so JavaScript is actually required to load in the adverts and programming in chunks.
• Turn off all Flash tracking by disabling Flash cookies. You do this by right clicking on a flash movie, click the Global Settings option and then choose "Block all sites from storing information on this". Unless you really want another way for advertisers and websites to track your online movements there is little need for this option to be enabled. You may want to check your video and microphone options as well.

Even after all this the Demand 5 flash videos were still having problems playing and although the options I just disabled are worth doing anyway to prevent online tracking by advertisers it didn't fix the Demand 5 TV catch up problem.

Flash is a well known CPU killer on websites and I have seen whole PC's crash due to one to many flash object on a web page being left open too long. Just open a page with a few flash movies and watch the CPU rise in your task manager if you want proof - Chrome seems particularly bad for this but despite this many sites continue to try and write their whole website in Flash which is a BAD IDEA!

However I did notice that the page that held the movie also contained a large number of other banner adverts that used both flash and animated gifs and I wondered whether there was some sort of problem occurring due to all the techniques advertisers now use to try and overcome advert blockers.

Basically websites or plugins use a timer to re-insert banners that have been removed from the HTML DOM by advert blocking plugins like AdBlocker which also uses a timer to remove any adverts re-inserted this way. Both sets of code doing the opposite to each other every split second - not good for performance!

Because both the advertiser and blocker are using the same methods to scan and modify the DOM constantly it basically turns it into one big performance nightmare in which your DOM is constantly being re-written on the fly. The less client code that runs the better KISS IT (Keep It Simple Stupid) for a multitude of reasons.

The Fix for the Demand 5 website Performance Problem

I opened Firefox and went to install a plugin I use on my other computer called Flash Blocker but I noticed a new plugin had been released called Image and Flash Blocker 0.7. I thought I would try it out.

At first I thought something hadn't loaded as I couldn't see any options under my Tools menu however you need to use the context menu (right click the mouse button) to use the add-on and see the various options.

Choose "Image and Flash Blocker" from the context menu and then select "Images off, Flash off" and hey presto most of the imagery, banner adverts, flash banners and movies disappear.In fact most of the Demand 5 page is blank without these features enabled.

The flash movies are replaced with a little red circle with a white "F" (for Flash) in the middle and if you want that particular flash movie to appear you just click it.

I turned every image and flash movie off on the latest episode of the show I wanted to watch e.g Burn Notice, NCIS, Archer, The Mentalist etc, and then I clicked the main movie screen to turn the video back on.

When the adverts had finished playing the TV show played without a single stall, stoppage or flicker. Hey presto problem solved! Big slap on the back for moi.

Remember - too much whizz bangery can cause performance issues

Remember images, Applets, Active-x objects, Flash and all the other fancy whizz bangery that comes with HTML 5, CSS 3 and modern JavaScript libraries is all well and good but more often that not it can cause a massive performance overhead on your computer. The best tactic is to turn it all off and then only turn on what you need once you know you need it and the clients browser supports it.

In the case of fixing Demand 5 catch-up TV it was definitely a case of less the better as it seemed that too much was going on behind the scenes to allow their TV shows to play smoothly. What exactly is happening I don't know without access to their source code but this is definitely a workaround for the Demand 5 performance problem that works!

Hopefully this blog article will help others overcome the same problem. I have tried writing comments with a link to this article on most of the shows I watch as they all contain similar complaints but for some reason they don't like the fact I put a link into my comment or try to help people solve their own technical issues.

So if you watch Demand 5 and have performance problems remember - turn off images and flash and then turn on the only flash movie you need - the TV programme you are trying to watch and then enjoy it without any flickering or stopping every 20 seconds.