Campaign for Digital Rights
Buying a new CD? Watch out for inferior imitations Tuesday December 18, 2018

Please note that these CD campaign pages have been frozen as of 14-1-2005, and will not be updated for the time being. However, they will still remain here as an information resource for people still encountering problems with their CDs.

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Corrupt audio discs, aka "Copy-Protected CDs"

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"Copy Controlled CDs" causing permanent damage to equipment

by Jim Peters, 30-Jun-2003

As maintainer of the corrupt-disc campaign pages on, I see a steady stream of corrupt-disc problem reports, and over recent months I have noticed a marked increase in the severity of the reported problems from people playing these so-called "copy controlled CDs" in their equipment. I have been hearing a lot more complaints about skips, pops and clicks on all kinds of devices (not just computers), and about cases where drives behave strangely after having been used to play a corrupt disc.

I believe that Macrovision (who now own Midbar) have stepped up the level of corruption on their Cactus-200 and Cactus-300 formats, and that this is what is causing the increase. I believe that they have found this necessary because of the large number of CD-ROM drives that can now deal with the corruption used in the previous versions of these formats. Unfortunately, with increased corruption, there is also a much greater risk of unpleasant side-effects, which in some cases means permanent damage to the equipment playing the disc.

Up until recently, we have heard of only a few cases of permanent damage to the drive, and often this was with older players. We guessed that the extra strain of handling a corrupt disc just pushed these old players over the edge.

However, we have now had a number of reports of relatively new drives which have been failing as a result of attempting to play a corrupt CD (see below for examples). It is well known that intentionally bad data on the disc can be used to cause additional drive strain or even total drive failure, for example by causing the head to attempt to seek off the edge of the disc, or by causing other abnormal usage patterns which drive mechanisms were never designed to handle.

Whilst in theory it is possible to write the drive firmware to protect the drive mechanism from 'malicious' data encoded on the CD like this, this would be similar to protecting a web server from crackers -- it is very hard to anticipate every possible form of attack in advance. This is made worse by the traditional approach to drive firmware, which assumes that CD manufacturers are not malicious and that they will only create discs according to the accepted CD standards.

However, this is obviously no longer true, with record companies all over the world now releasing discs specifically designed to cause problems for any computers that attempt to read them. I think it would be fair to compare the Midbar and Macrovision engineers to 'crackers' attempting to find weaknesses in our computer CD and DVD drive firmware that they can exploit in their disc formats, with the record industry sponsoring and actively encouraging their efforts.

Please note that I am not suggesting that Macrovision is intentionally trying to destroy drives (although damaging equipment was one of the benefits claimed in Midbar's original patent). They quite possibly see it more like collateral damage: "If we are going to make a disc which fails to copy in 70% of drives, then we have to accept 0.1% of them blowing up", or something like that. As they make their formats more unpleasant, it becomes more and more likely that there will be 'casualties', i.e. drives which get too confused with the invalid data and keel over and die with the strain.

This is a most unfortunate state of affairs, to say the least. However, now that it has got to the point where it seems that permanent and costly damage is being caused to consumers' equipment, I really think that we need to put a total stop to this. It is time to tell the record companies once and for all that we are not going to take any more of this nonsense.

We want our genuine original standard audio CDs back.

So, what can we do about it?

The most obvious thing is simply to not buy corrupt CDs any more, and to return corrupt CDs bought accidentally -- and to make sure that the label knows about this. We want them to know that there are plenty of people out here who will not consider buying "copy controlled" discs ever again.

It is also important to push for the online retailers to give full warnings on their websites for all the corrupt discs. At present many do not include warnings at all, or only if forced to by customer complaints. I have been trying to improve the situation with our 'retailer' campaign page here:

We really do need plenty of consumer pressure to make these online retailers wake up and give us proper warnings before we order the CD. If you regularly use an online retailer to buy your CDs, then send them an E-mail and let them know that you are a regular customer and that you need to see full and clear warnings about all "copy controlled" discs before you will buy any more music.

If you have suffered a drive failure as a result of using a corrupt disc, then please see if it is possible to demand compensation from the retailer for the replacement drive. In some countries this may be possible through the small claims courts. You may need to find a local CD drive repair engineer to look at the drive to back up your case. Retailers would very soon think twice about stocking intentionally faulty CDs if they started having to pay for the damage they cause.

Apart from that, there are very many non-computer users out there who are buying CDs and who still don't understand the problem. We need to get the information out there to them (and get the news into more mainstream channels). Many of our pages and leaflets (e.g. this one) might be of use as supporting information.

I really think that we need to finish with "copy controlled CDs" for good. Right at the beginning of this problem, Philips predicted that "copy controlled" disc formats would not last beyond a year, and yet here we are nearly two years on still putting up with this nonsense. It is time to tell the record companies to put an end to this once and for all.

-- Jim Peters, CD Campaign Coordinator


Here are some of our recent reports. We have heard from a number of people who have found that normal CDs won't play correctly in their drives after attempting to play a "copy controlled CD". In some cases the effect is temporary and after some period of time the drive does recover and play normal CDs once again. In other cases the damage appears to be permanent and the drive does not recover.

Often the person reporting has said "maybe this is just a coincidence, but it would be a very large coincidence", and I agree. Given that people often notice their drive making unusual noises when a corrupt disc is inserted, it seems clear to me that this is not a coincidence and that corrupt discs are indeed causing these failures.

For example:

  The DVD ROM drive in question was less than a year old and was
  working fine up until the time of playing Tubular Bells 2003 with
  the copy protection.
  Since playing that particular disc, it developed problems reading
  other discs and a short while later, it finally locked and wouldn't
  eject on trying to read a disc.
  I noticed a burning 'electrical' type of smell emanating from the
  drive itself.  I promptly switched off the computer.  I've since
  replaced the drive and took the copyprotected disc back to the local
  Virgin store where I purchased it, backed up with the original
  receipt.  I explained to them what had happened and also produced
  the invoice issued for the new DVD ROM drive, to which they gave me
  a refund.  [Ed: The refund was on the disc, not the drive.]
  What I particularly feel miffed about is the sheer contempt with
  which these record industries treat their customers and what is sad,
  is that this particular CD is a great piece of music.  Incidentally,
  I've subsequently purchased a non-copy protected version of this

And here is another:

  Well, it's a Pioneer DVD-116 drive, and it used to work fine, up
  until I tried to play the Tubular Bells 2003 disc.  The drive spent
  a long time, up to a minute, trying to "pick up" the disc, where it
  spun up and down again repeatedly, and made rather disturbing
  clicking noises. (Which it does not normally do.)
  Eventually I gave up and punched the eject button. Since then, the
  drive has never worked properly.  It *does* still read CDs, just,
  but now it takes a very long time to recognise that you have put a
  CD in, and will sometimes "drop" a CD, and have to spin it down and
  up again before it will continue to read.
  It is of course quite possible that this is all coincidence, and
  that it stopped working just before I tried the Tubular Bells 2003
  CD, but that would be an awfully large coincedince.
  The CD has since been returned for a refund.

And another:

  My copy of Dido, No Angel (with bonus track, Take My Hand),
  purchased through, appears to be a classic copy-protected
  cd.  When inserted into my matsushita dvd/cd-rom drive, non of the
  tracks are recognised, but even more insidiously, after the failed
  playback of this cd, the cd-rom drive itself will not recognise ANY
  music cds for a random lenght of time.  When I posted a question on
  the subject on to the Dell Community Forum, identifying your website
  and simply asking if any other users had experienced the same
  problem of time-locking, my post was censored.  And a post from Dell
  stated 'dell does not permit users to post hacks or other 'not
  exactly legal' methods on its boards.  A second post I made that
  responded to another users problem with non-playing audio cd's, by
  suggesting copy-protection may be the cause, was also deleted.

And another (a standalone DVD player):

  Hi, I found your site after having problems trying to record Audio
  Bullys album "Ego War" I then found it to be "copy controlled" with
  a sticker on the case and some information on the back of the
  sleeve.  The main problem I am a tad p****d off about is that my DVD
  player now refuses to play any of my old cds properly!
  Now this could just be a coincidence, but is it? When I play a cd it
  will play maybe 3 - 4 tracks and then loose all data and it cannot
  find the toc or any info to play.  The DVD player is a Marantz
  DV4100 and I am in the process of trying to figure if the player is
  faulty or has it been corrupted by this ridiculous copy control.
  When I finally manage to get in touch with marantz I hopefully will
  find out.

Also see this Mike Oldfield discography site which has been monitoring the situation with the "Tubular Bells 2003" disc specifically.