7MC DVB-S Signal Breakup

DJBenson

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Hi all

I've recently resurrected my HTPC in an attempt to scale back my outgoings (dropped Sky subs). It's all working relatively well apart from the fact that I get picture breakup on various channels (including BBC1, ITV1, C4 and Five).

The first signs of this were on the HD channels which were almost unwatchable - this was using a motherboard with integrated ATI HD3200 graphics so I upgraded to a discrete card (ATI HD5700 series) and this made things better - the only breakup I tend to get on the HD channels now is immediately after skipping (fast forward/rewind) - I would be interested to know if anybody else gets this.

The main issue though is breakup of the SD channels - on average, it occurs every 10 minutes or so and is evident in the broadcast (as recorded TV displays the breakup at the same point when played locally and over the network).

I've included my spec below for reference and would appreciate any tips.

Gigabyte GA-MA78GM-SH2 (onboard A/V disabled)
AMD Athlon AM2 4450e dual core (2.3Ghz)
4x1GB memory (~3GB accessible)
Asus 1GB ATI HD5570 PCI-E Graphics
Samsung HD204UI HDD (firmware NOT updated yet)
Blackgold BGT3595 DVB-S2/DVB-T PCI-E tuner
Windows 7 Ultimate
 
I've heard something about signal offset which made me wonder if that could be the issue - does this ring true at all? How do you amend signal parameters in 7MC (manually amend channel frequencies)?
 
Investigate power-saving options, it may be the graphics throttling back clock rates or even the cpu to reduce power loading.
 
Already checked those and there's nothing (AFAIK) that should cause me issues;

Link State Power Management = Off
Hard Disk = Turn off after 20 minutes
Processor Power Management = 100% Min/Max (although the "Cooling" option is set to "Active")
Display = Turn off after 120mins
Multimedia When Sharing Video = Allow to Enter Away Mode
Multimedia When Playing Video = Optimize Video Quality

Anything amiss here or some other setting I've missed?
 
Also just checked the AMD settings and there are no power-saving options enabled there either.

Would a graphics card issue really affect the transport stream being written to disk?
 
I have a similar problem to this. I am using a revo 3700 with 4gb ram. I find that i can watch all channels but every so often the picture will go blocky. This also happens if i am just recording not watching and then playing back on a different machine. I was starting to wonder wether it is my sattellite signal, which according to my old sky box is about 2/3rds quality and strength. My old sky box does not get blocky pictures though. Could it possibly be the dvb-s box itself? it is a usb tbs q-box dvb-s2.

Cheers, james.
 
I've had this problem. Same issues with the same channels. This post made me look at my power settings. I have fixed my signal breaking up my setting PCI Express -> Link State Power Management to Off.
Inital tests seems to have fixed the problem :)
 
I've had this problem. Same issues with the same channels. This post made me look at my power settings. I have fixed my signal breaking up my setting PCI Express -> Link State Power Management to Off.
Inital tests seems to have fixed the problem :)

Unfortunately this didn't work, I have since looked in the windows logs and found that logmein was having a problem resolving a DNS lookup. I have uninstalled logmein and it seems to be lot better. I'll report back in a week.
 
That didn't work for me either. The BBC HD channels are almost unwatchable now due to picture corruption (especially on high movement video).
 
I used to get severe blocking/breakup when using my integrated gfx. With some help I managed to work out that this was drivers that didn't support DXVA. I replaced the card with a cheap NVidia card and the blocking/breakup vanished in an instant......

Hope this helps!

edit: this is what mine looked like Blocking
 
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No it's not the graphics either - I upgraded from the onboard 3200HD to a dedicated 54xx (5450 IIRC) which should be plenty - no HD and poor SD despite very good DVB-T/S signal strength/quality.

A bloody Sky box does this stuff without breaking sweat - why is it so difficult for a decent-spec HTPC to do the same :mad:

EDIT: Monty - that blocking is exactly what I get - generally on high motion scenes but it's quite obvious most of the time. The sound remains perfectly throughout.
 
No it's not the graphics either - I upgraded from the onboard 3200HD to a dedicated 54xx (5450 IIRC) which should be plenty - no HD and poor SD despite very good DVB-T/S signal strength/quality.

A bloody Sky box does this stuff without breaking sweat - why is it so difficult for a decent-spec HTPC to do the same :mad:

EDIT: Monty - that blocking is exactly what I get - generally on high motion scenes but it's quite obvious most of the time. The sound remains perfectly throughout.
This is a driver issue. Originaly discovered by ATI users but now also with onboard Intel's. I believe if you look hard enough you might find a cure for it, maybe the Omega drivers if they are still around?

Replace with a cheap NVidia and it will go away. Thats the route I chose and for £30(?) it was worth EVERY penny.

p.s my pc can cope with 3 HD streams, 2 of those are Sky HD feeds and its only an I3. :thumbsup:

edit: Something to do with Direct X Video Acceleration/H264. If you can, try turning this off in your drivers control panel?
edit2: Intel have now released drivers (for my motherboard) that cure this but, thats not much help to you i'm afraid.
 
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Unfortunately this didn't work, I have since looked in the windows logs and found that logmein was having a problem resolving a DNS lookup. I have uninstalled logmein and it seems to be lot better. I'll report back in a week.

Well, i can confirm that i have had an evening free from the signal breaking up. I have even gone back to DVB-T which was completly useless for me:clap:

I understand that this solution wont help every one but it may help someone.

I suggest that you look in the windows logs, see if it highlights any issues.

I original, got my first clue to my problem when i turned off my router for a reboot. My signal instantly cleared up. This is when i started to look at hardware problem and thought i might be the network adapter. However i believe logmein installs software network adapter, this was reporting error in the windows logs. So I removed the offending SW and my problems were gone:D

I hope this my help other

btw, i have an nvidia 8600GT

Pete
 
This is a driver issue. Originaly discovered by ATI users but now also with onboard Intel's. I believe if you look hard enough you might find a cure for it, maybe the Omega drivers if they are still around?

Replace with a cheap NVidia and it will go away. Thats the route I chose and for £30(?) it was worth EVERY penny.
I had a lot of problems with break up on an ATi4550 card using BBCHD - the solution was to roll back from the 11.5 release of the ATi Catalyst Control Centre and drivers to the 11.4 release.
Many others have seen the same issue with their cards - well worth a look the drivers are available at the ATi website.
 
I am 50% in to removing the 11.6 drivers (as in I've run the Catalyst Install Manager and used the "Quick Uninstall All ATI Products" option) but when my HTPC booted, it still had graphics drivers (and HDMI sound) and even more confusingly, BBC HD/BBC One HD are 100% stable!!

I've no idea which drivers it's currently running but they are perfect!
 
More than likely it has defaulted to Windows Update and pulled down the MS Windows Update drivers.


As they say, don't fix what aint broke! :thumbsup:

Be aware though that a MS update in the future might over-write them and bring the issue back if this is the case.
 
That's what I thought but I disconnected from the internet to stop this from happening so they must be the default/out of the box drivers - either way they are working superbly.

Also noticed that the "Signal Quality" meter in 7MC (for the DVB-S signal) is 100% where previously it registered about 70% :D
 
That's what I thought but I disconnected from the internet to stop this from happening so they must be the default/out of the box drivers - either way they are working superbly.

Also noticed that the "Signal Quality" meter in 7MC (for the DVB-S signal) is 100% where previously it registered about 70% :D

Great news either way!

Just be warey that as soon as WUpdate runs it will try to "upgrade them".
 
Cool, job done then :thumbsup:
 

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