SkyTV VIII issue

[okrisz]

Hi,

I have 2 Sundtek SkyTV sticks.  One older version (version VI)  and I just received a new one which is version VIII.

I have no problem with the old stick on a raspberry 3 B+ using Libreelec and Tvheadend. Everything works just fine.

But when I replace the old SkyTV stick with the new one I have issues on HD channels. (I updated the Sundtek driver)  I have a lot of Continuity errors and the stream stalls for 1-3 secs regularly so any HD channel basically unwatchable.

What do you suggest to do?

[Sundtek]

Hi,

can you join the chat?

https://support.sundtek.de/chat.php

also which transponder?

[okrisz]

Thor 1W   -   DVB-S Network/12034.36V/Nat Geo Wild HD

[Sundtek]

In Detail (just for us):
SIGNAL: [.............................    ] ( 89%)
SATQUALITY:  72% 
SNR:  10 
BER:      0
FREQ: 11842560   KHz
LOCKED: YES
SYS: DVB-S2
SYM: 30000000
FEC: FEC_3_4
MOD: PSK_8
VOLTAGE: V(13V)
TONE: ON

> FE00 - RECEIVED DATA WITHIN 1 SECONDS 8386560
RECEIVED DATA WITHIN 1 SECOND: 8386560

[Sundtek]

We have not seen that issue before on the raspberry PI, however increasing the cpu frequency improved or fixed that issue.

either
* in the config.txt or
* mediaclient --cpupush=performance
or (in case mediaclient is not found):
* /opt/bin/mediaclient --cpupush=performance

[okrisz]

I am still suffering from this issue. The mediaclient --cpupush=performance  does not solve the issue.

I wrote several emails to support but no response. My old SkyTV ultimate 6  stick does not have this issue. I don't know what to do.

[Sundtek]

I think this is a Skytv 8A issue.
We have only manufactured around 10 units of those and went for SkyTV 8B afterwards since the manufacturability of the first revision was too difficult.

However for the Sky 8A units /opt/bin/mediaclient --transfermode=iso should fix the problem (but I will evaluate that within the next days). The default is transfermode is --transfermode=bulk

SkyTV 8B and ongoing use different chipsets with larger buffers and were released around October 2018.

[okrisz]

transfermode=iso didn't fix the issue
I also set nullpackets=on as the doc says

[Sundtek]

Isochronous is not delivering any data on your system right?
I will check that at the beginning of next week.

This SkyTV 8A is using the same chipset as the DVB-C tuners but the bandwidth of DVB-C is much lower.
SkyTV 8B (USB 2.0) and following (which include multituners) are optimized for bandwidth up to 360 mbit (on a Raspberry PI). Multituners are FPGA based including a lot buffer memory.

[okrisz]

Isochronous is not delivering any data on your system right?

I dont know what I have to check for that.

[okrisz]

I purchased an Odroid N2 and the tuner has the same issue.
Only my SkyTV version 8 tuner has this issue. The version 6 is ok. I am very disappointed and now that I receive absolutely zero support. I wrote several emails and no response.

[Sundtek]

What no support? I guess you have no idea how much time we have put into the Ordoid-N2 already in the past and it all end up to be an issue with the Amlogic Chipset which we have seen years ago already with another cheap chinese Android system.

The Odroid-N2 has been identified as troublesome already, only the OTG port seems to work, also there's a discussion about that in the Hardkernel forum.
One customer even received a new board from Hardkernel there's a chipset issue with this board, they could not fix it either, and the problem happened with several USB gadgets.

Amlogic is the right entity to solve your issue, however Amlogic has licensed the USB Core and they aren't into that issue either. So the issue has to be passed further down the line to the design house of the USB core.

If the issue can be backtraced that it's our issue we'll certainly try to support and fix it.
For now I'd say you might try to use a USB Hub on the OTG Port or try to use our Dual DVB-S/S2/S2X USB Tuner on it.
Avoid the other ports for just about anything (including USB Storage since some Odroid users also reported corruptions on USB harddisks).

[okrisz]

How can you explain that the SkyTV version 6 works without any problem but the version 8 does not? This is what is happening. I used this tuner first on RPI 3 B+ and now on Odroid N2.

Again, SkyTV 6 works but SkyTV 8 does NOT.  I can understand that there are issues with Odroid but this still does not explain why the version 6 tuner works perfectly and the version 8 does not.

[Sundtek]

I think I remember, you are using an earlier version of the SkyTV 8 using the same USB Chipset as the SkyTV 6, but newer DVB-S/S2/S2X receiver.
Your version is equivalent to SkyTV 8A; while all the followup retail versions are SkyTV 8B with a completely different USB chipset.

And the problem only happens with a particular transponder, exceeding a certain bandwidth no?

However one thing to note about the Odroid N2 is that only that one seems to have some HW issues on non-OTG ports (also the SkyTV 6 should have issues every now and then on the other ports).

[okrisz]

Yes, the problem occurs on transponders exceeding around 5-6000 kb/s bandwidth.
I tried to set transfer mode to iso as well but that didn't help. I think this SkyTV 8A has some kind of defect. I would gladly replace it with a SkyTV 6 since that one is perfect.