[mythtv-users] cannot schedule both tuners on AVerMedia Twinstar

Stephen Worthington stephen_agent at jsw.gen.nz
Sat Jul 31 03:25:22 UTC 2021

On Sat, 31 Jul 2021 11:29:56 +1000, you wrote:

>I had this USB tuner for a long time but decided to use it again now. Plugged it in and configured
>the capture-card and input-connection. All tuners (there are 5 others) show up and can be tuned into in WatchTV.
>The wiki says "unsupported" but it was last updated in 2014 so probably out of date?
>The problem is with scheduling. I have the two Twinstar tuners set to almost the same priority.
>myth refuses to use both, so (depending on the order I set) it will allow scheduling from one
>and will not schedule on the other at all. I can change the priority to have it pick the other
>and it then will never use the first.
>I am sure that this device has two independent tuners. It shows up as two devices in /dev/dvb/.
>It shows up as two in mythtv status (actually each tuner shows up as 4 by reclimit).
>Looking at mythtv coming up I notice:
>CoreContext cardutil.cpp:1173 (SetDeliverySystem) - CardUtil[29]: Set delivery system: DVB-T
>CoreContext cardutil.cpp:1173 (SetDeliverySystem) - CardUtil[33]: Set delivery system: DVB-T
>CoreContext cardutil.cpp:1173 (SetDeliverySystem) - CardUtil[37]: Set delivery system: DVB-T
>CoreContext cardutil.cpp:1173 (SetDeliverySystem) - CardUtil[41]: Set delivery system: DVB-T
>CoreContext cardutil.cpp:1173 (SetDeliverySystem) - CardUtil[45]: Set delivery system: DVB-T
>CoreContext cardutil.cpp:1173 (SetDeliverySystem) - CardUtil[50]: Set delivery system: DVB-T
>CoreContext recorders/dvbchannel.cpp:699 (Tune) - DVBChan[50](/dev/dvb/adapter-OPEN-ELEC-6/frontend0): Next tuning after less than 1000ms. Delaying by 1000ms
>CoreContext cardutil.cpp:1173 (SetDeliverySystem) - CardUtil[51]: Set delivery system: DVB-T
>The first cards (29-45) are the "older" USB tuners, 50 is the TwinStar does not schedule and
>51 is the other tuner on the Twinstar that does schedule.
>I looked over my settings and they look good to me.
>I do notice One unusual message (see below). Is it related?
>Bootup messages that may be related:
>usb 1-4.4.2: New USB device found, idVendor=07ca, idProduct=0825, bcdDevice= 2.01
>usb 1-4.4.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
>usb 1-4.4.2: Product: A825
>usb 1-4.4.2: Manufacturer: AVerMedia TECHNOLOGIES, Inc.
>usb 1-4.4.2: SerialNumber: 0000000000000
>dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered.
>usb 1-4.4.2: dvb_usb_v2: found a 'AVerMedia Twinstar (A825)' in warm state
>dvb_usb_af9035 1-4.4.2:1.0: Device may have issues with I2C read operations. Enabling fix. <<<<<<<<<<
>usb 1-4.4.2: dvb_usb_v2: will pass the complete MPEG2 transport stream to the software demuxer
>dvbdev: DVB: registering new adapter (AVerMedia Twinstar (A825))
>usb 1-4.4.2: media controller created
>dvbdev: DVB: registering new adapter (AVerMedia Twinstar (A825))
>$ uname -a
>Linux e7.eyal.emu.id.au 5.13.5-200.fc34.x86_64 #1 SMP Sun Jul 25 16:19:01 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
>$ mythbackend --version
>[see attached file as requested]

I have a Kworld DVB-T 399UR dual DVB-T USB tuner, and on it both
tuners work, but due to some common hardware that is used by both
tuners, you can not use both tuners at once in Linux.  It works fine
in Windows, which is where I am now using it.

With your tuners, have you tried setting up manual recordings with the
tuner specified manually?  In LiveTV, what happens if you manually
switch to the problem tuners?

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