[mythtv] Multiple Tuner Issue

Carl namuch at namuch.net
Thu Sep 15 13:55:13 UTC 2005


I've searched all the lists and documentation to find the answer to this
and come up short, so I thought I'd mention it here to see if it really
is a bug before I report it.

I've been using mythtv with a single PVR250 for about a year, I just
added firewire support to get HDTV and digital channels using an
SA3250HD.

Everything works fine unless I attempt to change the channel (while
watching live tv), to a channel that is only available on the tuner that
is not currently in use.  Mythtv seems to ignore the channel change
request unless that channel is assigned to the currently active tuner.

Here's where it get's interesting:  if I change channels by using the
EPG, then mythtv actually switches tuners like I would expect and tunes
to the new channel.

If I use the manual tuner toggle controls, it swaps tuners without issue.
 It only appears to have a problem when a new channel is keyed in
without the EPG active.

I traced the code a small bit to TV::ChangeChannelByString() and the
calls to ShouldSwitchToAnotherCard() and GetValidRecorderList() are both
failing (showing that all tuners are in use when they're obviously
not), when the EPG is not active.

Is this a bug? Or am I missing something that should be obvious?

I'm having difficulty debugging it further, 'cause the machine in
question is in full time use and I don't want to de-stabilize it (any
more than running bleeding-edge code already does).

I'm on the current cvs (to get the firewire with SA3250HD support), and
I have two separate channel profiles that I fetch from zap2it that are
filtered so each of the tuners only get the channels that apply to them.

If anyone else can confirm this is a bug, or tell me what I'm missing I
would appreciate it.


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