DNTV Tiny USB2 ok on MCE2005 not Vista Ultimate

[agent86oz]

I have an older computer GA-8IPE1000 Pro2 MCE2005 2.4 Pentium ATI 9600 AGP video card 1G ram and it will run 2 x USB2 tuners and a Compro T300 with no reception or recording problems at all even if I run all 3 tuners and play a recorded source. I am only using Standard definition at the moment due to the space of the files, limited HD broadcasting and though a good LCD Panel it is not 1080i but it can pretend it is by downscaling ;-) At 37" 1080i would be probably overkill anyway.

I have a much newer 3.0 Duel Core Processor on a Gigabyte motherboard GA-8I945P-G and a PCI-e nVidia 6600 video card and 2G ram. With the exact same antenna leads and tuners connected I get regular video jitter where the video will pause then jump forward and sometimes jump forward then back for about half a second (I am stills struggling for for a concise technical term for the different types of video jitter, stutter so I hope the explanation is usefull :-). Ok I had a backup of the clean Vista Ultimate install before tuners or other software installed so I went about some trouble shooting.

I plugged 1 tiny usb2 tuner in and maybe 4 or 5 glitches an hour. I put two in and that increased maybe to 6 times an hour and I tried different USB ports. Sometimes when two tuners are running the recording will be so bad that it is almost unwatchable.

The CPU use is well below 10%

I guess because of the 2G ram that is why the HDD led blinks a lot less than the other computer as it is probably buffering more before writing to the disk.

Ok the digitalnow website showed a BETA driver but when I looked it showed only XP driver after I clicked the vista link but I took a punt and installed it. It is only marginaly better. I have a Toshiba Duel tuner HDD J34 PVR and it works fine off the same spliter except the occational ABC low signal which is due to a poor repeater so I ignore that channel in tests.

This newish computer Vista Ultimate blitzes the MCE2005 computer in speed so I think there must be an incompatibility issue with the drivers and Vista or something weird with my hardware. The problem is recording and not playback as all my MCE2005 recordings can be copied to the vista computer and play perfect.

I have posted previously about an unsmooth playback on the nVidea card but as I mentioned in that thread it was fixed by making the TV the primary display. That was a all the time issue where movement on the screen looked like it had terrible response time and would jerk when the picture would be panning.

This problem is random and from half a second to many seconds.

I have not tried the Compro PCI tuner again.

Would PCI-e twin tuner be more reliable? From what I have read the only time USB should be a problem is 3 or more tuners recording HD not SD.

Setting up a Windows Media Center PC certainly is not for the average person, it burns a lot of time.

[impact]

Burns a lot of time ? .... and Money !!!

I use the same twin usb device in my MCE machine running Vista as my Tuner 5 and 6. The first 4 tuners are PCI-e digitalnow s2's.

While I have no problems with the tinuy USB's - and I only used the driver that was downloaded from windows update, the S2's are far superior... Of the 4 leads into my MCE machine, 1 is marginal - if I have that plugged into a sub tuner, it suffers stutter, plug it into a S2 and I get no stutter... So - yes the S2's are better than the USB's....

Not sure who told you about problems with USB's and SD / HD recording past 3 tuners... In the past (MCE05) I have had 5 USB tuners running - no issues... Your not filling the USB bandwidth by any stretch - your pushing other items like HDD throughput - but USB should be fine.

Not sure what to suggest about the USB problem and stutter your having... besides trying another card like the S2 to see if it solves the problem and then the USB's could be used in a secondary machine or ebay'ed... I'd look at drivers first though - both the usb and video card ones....

Maybe even think of the not so obvious - motherboard bios ? Drivers / parameters relating to the USB bridges / hdd etc...

Keep perservering and i am sure some others more knowledgeable on your particular board might offer some suggestions...

[agent86oz]

Thanks for that. I rang Renura at digitalnow to check out the differences between usb2 vs the PCI-e tuners he was selling and he said their was no difference in quality and reception but it was about a 40second phone call as he prefers forums and email. I actually did try email with no reply first for 2 days before I rang though, I think he just likes the forums as he seems quite active ;-) As the Vista Box sits next to the MCE2005 box for testing I have just unplugged and used the two USB2 tuners without disconnecting the antenna and every time it works great on 2005 but not on Vista. I chose the USB2 tuners so I could see if I could get my older computer working that did not PCI-e and if it did not then I could use the tuners in the newer computer. Sounded like I had more options. Renura you don't want to swap a couble of USB2's for the PCI-e do you, boxes and remotes perfect, tuners scuffed a bit ;-) Please not I am not having a go at Renura and the tuners turned up the very next day to a country destination when ordered late the previous day.

[renura]

We have sold many thousands of these tuners in Australia alone, I would say 1/2 of them are used with MCE and at least hundreds with Vista. We have not heard of anyone having the issues you're reporting, I myself use two of those on Vista Ultimate based PCs and work perfectly, so I doubt it is the device driver. Try and use the same decoders as you use on your MCE machine, see if that makes any difference. It could also be interference in your Vista PC (nothing to do with the OS, more like the hardware you are using)?

One thing you can try (if not done already) is to record a show, without viewing it, then play it back (on the same PC as well as another) and see if you notice the glitches?

[agent86oz]

Ok Renura thanks for the quick reply. Sounds like it could be hardware as I have now recorded on the Vista Computer like you said and played back the recordings on MCE2005 witht he same problems so it is not recording properly and not a Vista playback issue. I trust you if you say that no one else is having problems as I have seen you are well respected on forums. What do you suggest to do on the hardware front? Should I buy a PCI USB card and see how it goes?

[renura]

Originally Posted by agent86oz

Ok Renura thanks for the quick reply. Sounds like it could be hardware as I have now recorded on the Vista Computer like you said and played back the recordings on MCE2005 witht he same problems so it is not recording properly and not a Vista playback issue. I trust you if you say that no one else is having problems as I have seen you are well respected on forums. What do you suggest to do on the hardware front? Should I buy a PCI USB card and see how it goes?

It is hard to know what the solution is, given that we don't really know what the cause of the problem is in the first place. In any case I would not recommed a PCI>USB card, under any circumstances.

I would try different USB2 ports to start with, perhaps a powered USB hub to see if its the USB ports in your PC that are the issue. But it could be other components that are interfering, noisy power supply, for example, are notorious for creating such problemes, so are some wireless devices, video card drivers, etc.

An interesting thing to do would be to install MCE on the Vista machine ad see if you get the same issue. On way of doing this would be to use another HDD and install MCE on it, that way you can keep your existing Vista installation, should the issue remain under MCE.

[agent86oz]

Thanks, that sounds like a good idea. Maybe I should have used your software ;-)

[agent86oz]

Ok I finally got these tuners working in Vista Ultimate or should I say my main PC. As I said they worked fine on my old MCE2005 box but not on the newer Vista box. The sound would be ok but the picture would drop frames and even play some frames backwards for a few seconds. The exact same antenna and splitter. Worked also on my Toshiba Duel tuner PVR. Renura suggested it was something to do with the computer.
I tried different USB ports with no change.
I had the signal strength on my antenna checked and it was on the low side but not bad but we put in a 10db UHF amplifier before the splitter and bingo it now works fine. I am guessing there is a bit more interference on the Vista box and it needed to have a bit more signal to improve signal to noise ratio.
To test further I restored the computer using Acronis drive image to a time where I had not installed nVidea driver, no nVidea PureVideo and the windows detected drivers for the tuners but everything still worked fine.
The problem is not related to any drivers and is purely a signal strength vs interference issue as far as I can tell. Sometimes you just need a better signal and I am guessing that it would be more of an issue if you had the tuner in the computer than using USB.
Is there a way of checking the signal strength or signal to noise ratio on tuners other than using an antenna signal strength meter? My satellite box give signal strength and signal to noise ratio although it is only a guide it is often a good indicator.
The problem was I assumed that the antenna system was sufficient because it worked with my PVR and the same tuners in another PC.
Thanks for the feedback everyone and I hope this may help someone troubleshoot in the future.

[renura]

On the CD that came with the product, there is a tool : "TinyMonitor.exe", which can help with tuning/adjusting your antenna, it displays a number of parameters related to signal characteristics, including SNR, BER, etc, for any given frequency, try it.