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-   -   Y2K7 bites many DVDRs with "DST bug"? (http://www.avsforum.com/forum/106-dvd-recorders-standard-def/846731-y2k7-bites-many-dvdrs-dst-bug.html)

wajo 05-12-2007 04:36 PM

I've seen lots of posts from people who have been having sudden and unexplainable problems, incl. freezing, non-response, channels lost, shows not recording, clock haywire, etc...so far, mostly Pannys and some Philips, but may be others, that have clock set auto and DST ON.

I've suspected a "DST bug" (not official...my term only) is causing many of those problems, and I finally found some technical explanation of the bug, officially called the "Year 2007 Problem" or Y2K7.

This Wiki entry explains how devices that have clocks need a TZ (Time Zone) ref. and that ref. must be updated in the SW/FW if the TZ rules changes, as they did for this year's DST start and end dates. That update is prob. what some DVDRs need to track time properly if set for Auto-Clock-with-DST-ON after the change?

Here's another Wiki entry that ref. "synching between devices that are aware of the changes in DST and those that aren't" in the 1st para. Example: people with a Sat or Cable box that gets updated to correct the Y2K7 Problem but the personal DVDR still has the old FW and clock/DST timing.

Here's one more entry that says this:
"There are two options for updating clocks. If your computer [ed. or DVDR] uses a time server to set the date and time automatically, you can simply adjust the time zone (in the Time Zone pane of the Date & Time system preferences) to a zone that is an hour earlier or later, as appropriate. If your computer does not use a time server, you can simply adjust the time in the Date & Time pane of the Date & Time system preference. Either way, there may be problems with software that calculates time internally using Coordinated Universal Time (UT, also known as Greenwich Mean Time or GMT)." (We know all TVGOS systems use GMT, so a problem there means timer recording problems.)

Here's a world map of the countries that use DST, no longer use it, and never used it. Note that Japan, China (essentialy all of Asia) either no longer use DST or never used DST. Might be a clue as to why they might not have programmed at least all of the 2007 NA units for the correct DST timing?

Lots more stuff in the Wiki entries to read if anyone is interested.

Final suggestion: People having inexplicable problems with their DVDRs should first try setting their clock manually and turning DST OFF to see if their unit has the dreaded "DST bug" (or "Y2K7 problem"). This problem could have started after the DST change or before, or whenever an STB or a host-station's DST SW received an update in DST instructions.

Note: Some machines, like Toshiba, call DST "Summer Time" in their menu system.

UPDATE... 5/18/07:

Several people have added a step that might be important: they first reset their units to factory default settings (pulled plug for >30 sec or used actual "reset" routine), then set their clocks manually and made sure DST was OFF.

If your unit is "frozen" or non-responsive, disconnect any inputs from cable or a Sat/Cable box, turn unit off then on again, and see if that releases it for your reset/clock changes. (If your signal source is creating the DST bug, this has a good chance of returning control to you.)

This might be worth a try if the simple manual-clock/DST-OFF changes don't work by themselves?

ncaahoops 05-12-2007 05:57 PM

Quote:
Originally Posted by wabjxo View Post

I've seen lots of posts from people who have been having sudden and unexplainable problems, incl. freezing, non-response, shows not recording, etc...so far, mostly Pannys and some Philips, but may be others, that have clock set auto and DST ON.

I've suspected a "DST bug" (not official...my term only) is causing many of those problems, and I finally found some technical explanation of the bug, officially called the "Year 2007 Problem" or Y2K7.

This Wiki entry explains how devices that have clocks need a TZ (Time Zone) ref. and that ref. must be updated in the SW/FW if the TZ rules changes, as they did for this year's DST start and end dates. That update is prob. what some DVDRs need to track time properly if set for Auto-Clock-with-DST-ON after the change?

Here's another Wiki entry that ref. "synching between devices that are aware of the changes in DST and those that aren't" in the 1st para. Example: people with a Sat or Cable box that gets updated to correct the Y2K7 Problem but the personal DVDR still has the old FW and clock/DST timing.

Here's one more entry that says this:
"There are two options for updating clocks. If your computer [ed. or DVDR] uses a time server to set the date and time automatically, you can simply adjust the time zone (in the Time Zone pane of the Date & Time system preferences) to a zone that is an hour earlier or later, as appropriate. If your computer does not use a time server, you can simply adjust the time in the Date & Time pane of the Date & Time system preference. Either way, there may be problems with software that calculates time internally using Coordinated Universal Time (UT, also known as Greenwich Mean Time or GMT)."

This last item specifically mentions a problem if the device tracks time in GMT, which we know many DVDRs do, esp. those with TVGOS.

Lots of stuff in the Wiki entries to read if anyone is interested.

Final suggestion: People having inexplicable problems with their DVDRs should first try setting their clock manually and turning DST OFF to see if their unit has the dreaded "DST bug" (or "Y2K7 problem"). This problem could have started after the DST change or before, where an STB or a host-station's DST SW got an update in advance of the DST change date.

I was worried about potential DST issues and confusion, so I did the last part, I turned DST off and changed the time manually. It's only twice a year, so its not a big deal for me...

wajo 07-02-2007 07:17 PM

I ran across this Panasonic page that describes the specific steps to take for specific Panasonic TVs, VCRs, DVDRs, etc. to cope with the recent DST changes.

Kelson 07-03-2007 09:42 AM

That's a pretty neat page. Couple of interesting notes about the Panasonic units: All the older HDD models with TVGOS get their clock set by TVGOS. Gemstar is providing the correct data. I can vouch for that, my E-85 had no trouble with the new DST change and changed time correctly at 2:00AM on the day it was supposed to.

I see the new EZ17 & EZ37 models are listed as having the new DST calendar. Since the EZ27 & 47 came out afterwards I would expect they have the new calendar also.

Final note: I have 2 old Sony VCRs hooked up and running that get their time signal from the local PBS station. They changed to the correct time along with the E-85 at the same time. They don't have any menu selection for turning on/off DST so they just get what the PBS gives them -- which in Philly happens to be the correct time.

Sean Nelson 07-03-2007 01:51 PM

Quote:
Originally Posted by Kelson View Post

the older HDD models with TVGOS get their clock set by TVGOS. Gemstar is providing the correct data. I can vouch for that, my E-85 had no trouble with the new DST change and changed time correctly at 2:00AM on the day it was supposed to.

My Pioneer 633 changed correctly, but the 533 did not. They both use TVGOS and are getting exactly the same signals via cable, so its a big mystery as to why the 533 screwed up. Despite repeated resets and fiddling with settings, it would not accept the "correct" daylight time until the following Wednesday, at which point it suddenly started working the way it was supposed to.

I can hardly wait for the fall...

crabboy 07-03-2007 05:28 PM

Quote:
Originally Posted by wabjxo View Post

I ran across this Panasonic page that describes the specific steps to take for specific Panasonic TVs, VCRs, DVDRs, etc. to cope with the recent DST changes.

Specific....uh huh..."Reset your machine, set your clock manually with DST off".
They've been reading this forum!

scottw383 07-05-2007 03:34 PM

Quote:
Originally Posted by Kelson View Post

I see the new EZ17 & EZ37 models are listed as having the new DST calendar. Since the EZ27 & 47 came out afterwards I would expect they have the new calendar also.

The EZ47 actually allows the user to configure the specific DST start/stop dates. For example, you can set the unit to recognize that DST begins on the 1st Sunday of April, or the 2nd Sunday of March, or whatever the government decides to change it to next. I guess Panasonic got tired of creating specific firmware for each potential DST change, and simply decided to make it "generic" and configurable against future changes...and I don't blame them. The default appears to be the current (2007) start/stop dates.

See P.63 of the EZ47 manual for a description of how this works. The manual (24MB .pdf file) is available on Panasonic's website, if you first navigate to the general DMR-EZ47VK page and then look under the "support & resources" tab.

jbesk 11-16-2007 09:41 PM

Thank you so much for the Y2K7 bug fix.

I have a LG DVD recorder with 1080i upconversion that always worked well until the last few months when we got some DVDs from the library they wouldn't play in the LG recorder but they would work in other DVD players and the DVDs were scratched. But today I bought Shrek the Third and it didn't work either so I knew it was an issue with the DVD recorder. After reading online for help (LG's website is a waist of time) and was about ready to give up I saw your message on the Y2K7 bug. I reset my settings to factory preset and turned DST off and manually set the time and tried two of the DVDs that didn't work before and instantly they both worked.

Thank you so much as you saved me about $200 because I was about ready to go to Best Buy tomorrow and buy a new DVD recorder. I can't believe this is the first I've heard about this DST bug. Amazing how something so simple can cause such an issue.

Desert Hawk 11-17-2007 12:06 AM

I don't understand how having the clock set incorrectly could possibly make a machine not play a disc or tune channels. It seems to me that the only possible problem an incorrect clock could create would be to not record a show you wanted and instead record what was on 1 hour earlier or later.
I freely admit that my knowledge of computer and AV tech is slim to none.

beekeeper 11-17-2007 02:51 AM

Quote:
Originally Posted by jbesk View Post

I reset my settings to factory preset and turned DST off and manually set the time and tried two of the DVDs that didn't work before and instantly they both worked.

You have two things that were done with the first, resetting the unit, being the probable fix. I doubt if DST had much to do with your problem. Anoth4er solution is unplug and wait for a few minutes, which does much of what the factory preset does.

golfster 11-17-2007 12:58 PM

Quote:
Originally Posted by Sean Nelson View Post

My Pioneer 633 changed correctly, but the 533 did not. They both use TVGOS and are getting exactly the same signals via cable, so its a big mystery as to why the 533 screwed up. Despite repeated resets and fiddling with settings, it would not accept the "correct" daylight time until the following Wednesday, at which point it suddenly started working the way it was supposed to.

I can hardly wait for the fall...

I never could get my Pioneer to set the clock automaticly so never had the issue.


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