Stumped by a 708A slowing on data CDs

vbimport

#1

I’ve been mostly happy with my 708A, but now and then it acts very oddly when reading data CDs. This problem usually occurs when I try to copy a full CD to my HD. The drive will grind to nearly a halt, sometimes after reading a large portion of the disc, sometimes right away. It tries to speed up for a second or two, but eventually it slows back down to a crawl. If I abort the copy and try again, it seems stuck in low-speed mode. It doesn’t recover until I pop the disc out and insert it again. But if I try to read the CD again, this story repeats itself.

The disc will eventually get read, but I don’t understand why it slows severely, and why the 708A can’t seem to recover its composure until I eject the disc.

I noticed this behavior when copying a backup CD-R, but it also happens with commercial CDs (for instance, when I copy my Windows XP CD to the HD, after about 350 MB it grinds to a crawl). Consequently I don’t think I’m dealing with bad source CDs. In fact, they read just fine in my generic Dell at work. Smaller CDs copy just fine because it only seems to happen toward the end of the CD (or after several minutes of continuous reading). [Edit: See update; the preceeding observation is not accurate.] None of the CDs in question are scratched or damaged.

What’s strange is that I have no trouble with audio CD DAE (I just extracted 50 CDs using PlexTools, many at 17-40X CAV), and I can copy commercial DVDs to my HD just fine.

Any help would be appreciated. I have the latest firmware (1.06) and I’m running XP (fresh install). I have an nForce2 motherboard, so I’m using the generic Windows IDE drivers instead of the ones from NVIDIA, which are known to cause trouble. The 708A is a slave on the secondary IDE bus (250GB drive is the master), but the problem also occurs with the 708A as the sole IDE master.

I wish there was a tool that could tell me what the drive is thinking when it slows down, because I’m out of ideas.


#2

I have the same story to tell about my 708A, only I was using CD-RWs. 708A slows down while reading CD-RWs which are actually readable very well on my LiteOn 166S DVD-ROM, with damaged blocks though (as shown by Nero CD-DVD Speed in yellow colour). LiteOn drive reads CD without slowing down, while Plextor drive slows down dramatically, then spins up, then down again and so on.


#3

It seems that the 708A has problems with CDs… read

http://club.cdfreaks.com/showthread.php?threadid=89083

When was your drive manifactured ?


#4

Originally posted by aberzins
I have the same story to tell about my 708A, only I was using CD-RWs. 708A slows down while reading CD-RWs which are actually readable very well on my LiteOn 166S DVD-ROM, with damaged blocks though (as shown by Nero CD-DVD Speed in yellow colour). LiteOn drive reads CD without slowing down, while Plextor drive slows down dramatically, then spins up, then down again and so on.

My initial thought was that the CDs were fine and my 708A was just behaving strangely, but I ran a CD Check in PlexTools and it slowed down in the same spot as the drive when it was reading. (The CD I tested was my original WinXP installation disc.) Despite slowing, PlexTools didn’t report any errors, so I’m not sure if that means there is a problem with the disc and the 708A recovered the data, or if something else is going on. I would almost be happy pronouncing this a problem with the CD since it happens in almost the same spot every time, but my LG drive doesn’t slow down. Then again, it could just mean my LG drive is careless and runs a higher chance of making an error. Without more information I don’t know if this is a problem or the Plextor’s smarts in action.


#5

My thoughts exactly.

708A wants to appear as very careful reader, at cost of reading time. But what is the benefit from that ? Result is exactly the same as reading on my LiteOn 166S drive, only it takes a lot longer. I havent got any CD yet which is readable on 708A drive and is NOT on LiteOn 166S drive. That means that 708A’s careful reading doesnt matter at all, if it can be accomplished with the same result by LiteOn’s careless manner, only sometimes a lot longer.


#6

I borrowed a friend’s brand new 708A to see if it also slowed in the same way as mine when reading my original WinXP installation CD (not a copy).

I swapped 708A’s in my PC and gave reading the disc in Nero CDSpeed a try. I was surprised that the new 708A completely choked on the CD! Mine slowed to 3x toward the end, but at least it could read it.

Despite only a few very small scratches, the new 708A gave me a “marker not found” error about 1/3 of the way through and gave up.

At that point I upgraded firmware (the borrowed 708A was 1.04 – the lastest is 1.06, same as mine).

After restarting I tried to read the CD again and this time it succeeded (go 1.06!), but it slowed much more than my 708A, and in more places. So I guess this excessive slowing on some CDs is not specific to my 708A. Hopefully future firmware updates will improve the situation. I’m glad it doesn’t happen on many discs.

I should also add that my earlier observation that “Smaller CDs copy just fine because [slowing] only seems to happen toward the end of the CD (or after several minutes of continuous reading)” is wrong. The pattern of slowing is repeatable for a particular CD and 708A, but it does not happen consistently at the end of the disc or after several minutes of reading. That was just a coincidence.


#7

The drive is designed to slow down in reading to give the best error free results. If the disc is difficult to read, the drive will slow down and repeatedly try to read the area until it gives up. Some commercial media is very poor quality due to problems with the dye or reflective coating, varying thickness of polycarbonate, eccentric (not on center) spindle hole, etc. The same disc may play well, i.e., audio, because audio is slow by nature in any CD drive. The same disc may read faster in another drive because the drive may do error correction differently (or not to the same degree) and give up with no indication that it had difficulty reading.

If you have access to a Premium drive, check the discs for C1/C2.


#8

This is a known problem. I had almost the exact same thing on my PX-708A. Please see the following thread:

http://club.cdfreaks.com/showthread.php?s=&threadid=82657


#9

Originally posted by Jucius_Maximus
[B]This is a known problem. I had almost the exact same thing on my PX-708A. Please see the following thread:

http://club.cdfreaks.com/showthread.php?s=&threadid=82657 [/B]

My issue may be related, but in the thread you linked, the complaints about the 708A having trouble reading all involve CD-R media. All of the CDs I’m having trouble with are pressed commercial discs (like the aforementioned WinXP installation CD).

I created CD-R copies of these questionable (though nearly mint) originals and my 708A rips through the duplicates at full speed.

If anything, my 708A seems very happy to identify and read my CD-R media (Mitsui). It’s just a few pressed originals that it doesn’t like.