AVS Forum banner

Status
Not open for further replies.
1 - 10 of 10 Posts

·
Registered
Joined
·
481 Posts
Discussion Starter · #1 ·
Hello,


I have an Audio Authority Digtial Audio Switch (model 1177) that takes the SBLive's coaxial digital out at input 1 and Digtial audio from my cable box at input 2. This switch can auto sense input and switch input sources based on priority. That is if the audio from the HTPC is on then the receiver would play HTPC audio. But, when the audio from the HTPC is not on then the cable box's audio would play. This used to work perfectly until recently. I do not know what the culprit is.


Currently, even if nothing plays on my PC the switch thinks that there is some audio signal coming out of the PC. This happens even if the audio is muted in windows audio control panel. But, when I shutdown the PC, the audio immediately switches over to the Cable box. When I power on the PC the audio again switches over to the PC input.


Another observation is, when I reboot the PC through windows restart I used to notice the audio briefly switching over to the Cable during BIOS boot up. Now even that does not happen. It behaves as if some sort of electrical signal is leaking through the SBLive's digital out.


What could be the problem? I have recently replaced my PSU. The new PSU is an Enermax 431W(P4)ATXEG465P-VE(FC).
 

·
Registered
Joined
·
481 Posts
Discussion Starter · #2 ·
^^^
 

·
Registered
Joined
·
13,423 Posts
Srikanth,


Switch inputs. Connect the PC soundcard to input #2 and the cable box to input #1. That way the cable box will override the PC.
 

·
Registered
Joined
·
481 Posts
Discussion Starter · #4 ·
Quote:
Originally posted by Cliff Watson
Srikanth,


Switch inputs. Connect the PC soundcard to input #2 and the cable box to input #1. That way the cable box will override the PC.
Cliff,


The cable box is always on as most of the time I watch either TV or ReplayTV. As long as the cable box is on, so is the audio coming out of it. It is the PC's audio that is rarely used except when playing DVDs or MP3s.


Therefore switching the inputs is not an option. I would like to know what's causing the AA switch to sense always on audio from the PC. In other words what is it that the digital out from SBLive sending out to the AA switch all the time?
 

·
Registered
Joined
·
13,423 Posts
â€Therefore switching the inputs is not an option. I would like to know what's causing the AA switch to sense always on audio from the PC. In other words what is it that the digital out from SBLive sending out to the AA switch all the time?â€


Srikanth,


The S/PDIF output from the soundcard is transmitting a carrier signal. Basically a 48kHz signal with zero packed audio frames. The AA1177 sees this as an active input and will switch to it depending on the input connector used.


For any input below #1 to be active the signal for all the input(s) above it must be turned off. For example I have mine setup with the soundcard to #4, RP-56 DVD player to #3, HiPix card to #2, and MyHD card to #1. To play music from the HTPC soundcard input 1 –3 must be turned off and if I turn any of 1-3 on it will override the soundcard.


With two devices always on you will have to manually switch inputs.
 

·
Registered
Joined
·
481 Posts
Discussion Starter · #6 ·
You amaze me from time to time with the wealth of your knowledge, Cliff.


OK. So basically I have two options. 1)Switch the inputs manually or 2) Switch the cable box off.


Do all soundcards send out 'zero packed audio frames'? I have two spare optical inputs on my receiver. May be I should get a sound card with optical out.
 

·
Registered
Joined
·
13,423 Posts
"OK. So basically I have two options. 1)Switch the inputs manually or 2) Switch the cable box off."


Correct

"Do all soundcards send out 'zero packed audio frames'? I have two spare optical inputs on my receiver. May be I should get a sound card with optical out."


If working properly all soundcards will output the carrier signal even oner optical.
 

·
Registered
Joined
·
856 Posts
I found this to be a problem as well. I have a DirecTiVo that always has to be on, a ProScan HDTV tuner that is always on, and an Xbox that has no remote on/off codes. It turned out that the autoswitching function does me almost no good.
 

·
Registered
Joined
·
3,858 Posts
Are you SURE you didn't accidentally didn't switch to manual instead of auto? Sometimes its the little things.
 

·
Registered
Joined
·
856 Posts
Quote:
Originally posted by chap
Are you SURE you didn't accidentally didn't switch to manual instead of auto? Sometimes its the little things.
Not sure if you were talking to me or the original poster, but I'm sure. The DirecTiVo needs to be on for my own reasons (I like to let it record stuff without me having to worry about it being on or off). The Xbox truely has no on/off function, and the ProScan is known to always send out an "on" signal.
 
1 - 10 of 10 Posts
Status
Not open for further replies.
Top