Muting Other Sound devices on startup

**rodweb** · 05-19-2009, 06:12 AM

Hope I go the right place to post. I got a minor problem with RR on startup becasue I am using the Silab USB radio and this DLL:

http://code.google.com/p/silabsradiodll/

but my problem is not restricted to Silabs and believe it or not, in this country FM (and even AM radio) are going to be around for a long time..

So anyway, here is the problem:

On startup, there is quite a lot of noise (eg. Background Hiss) which I have traced to the Silab by disabling all other sound devices in the system. The moment I press the Music button on the BMV2 skin the hiss dissappears. This behaviour is still present on the latest release.

It would appear that when the music player is selected all other sound devices are muted.

So would it be possible for RR to mute these other devices on startup (or whatever RR does when the music player is selected to mute the hiss)?

Alternatively, is there a command that could be embedded into the BMV2 skin to kill the hiss?

**mitchjs** · 05-19-2009, 10:20 PM

im not sure there is any issue here....

if you dont have say, xm or sirius, what lines that are muted before RR is started
stay muted
RR doesnt mute or unmute anything explicitly on start

and this statement is odd

It would appear that when the music player is selected all other sound devices are muted.

what are other sound devices?

my guess, the silabs fm tuner(someone get me one) brings its audio in via usb audio, and that dll uses directshow or some capture method to bring audio to the speakers

**rodweb** · 05-19-2009, 11:57 PM

Mitch, with the Silab installed, a new sound card appears in the Windows Mixer(Options/Properties/Mixer device). It also appears as a sound controller in device manager. I had to disable the device in Device Manager to make the noise go away. I'll check some more details but it could be USB Audio. Muting it in the Windows Mixer had no impact.

With Silabs enabled if you start RR, the moment you press the Music Player button in menu.skin, the noise cuts out and I have clean sound. So what does RR do at that point it does not do when starting the player on startup?

**rodweb** · 05-20-2009, 03:43 AM

Ok the device is called USB Audio and the sound card is called FM Radio

**mitchjs** · 05-20-2009, 11:51 AM

SOUNDS LIKE the SILABS DRIVER IS capturing audio and sending it to the WINDOWS PLAYBACK DEVICE

nothing happens special when u play music, other then the music playing

the problem is in the that silabs dll.. it prob shouldnt send any audio data to the playback device, unless its told to

i have in my mind how that dll and its audio works... but without having a sillabs tuner, im prob not going to be able to fix anything in that DLL

if u stop music (pause winamp), do u hear the hiss?
it can also be that the RR plugin or what ever RR does to talk to the silabs, has told the silabs to shut up... i dont know

i really only EVER focused on HD Radio

if i get one of these tuners, i might be able to play

**mitchjs** · 05-20-2009, 04:13 PM

fyi, i just purchased the silabs....

**mitchjs** · 05-27-2009, 05:49 PM

rodweb, how are u managing audio for the silabs..

its just a audio capture device, my self, i prob would avoid directshow
and capture it... the winamp line-in plugin would do it

for sure NO hiss when i start RR, no fm at all till i decide how i want to manage the audio from it

**mitchjs** · 05-27-2009, 05:57 PM

the .dll might and claims it has a directshow filter for audio...
it doesnt work for me... i hear nothing
course its documentation and example has a lot to be desired

i feel for anyone who is using this tuner on a CAR PC... the directed/visteon much better
at least for us folks in USA

**mitchjs** · 05-27-2009, 06:15 PM

stinking tuner doesnt shut up when its hw is closed...
i added a mute...

i dont for sure see any issues
with open audio, but im not getting any directshow playback here
im manually capturing and listening to it (a program i wrote)

BUT the tuner in MUTE, capturing has HISS!!
(but volume has to be very loud)

i havent found a OFF for this tuner

Even thier (silicon labs demo program, when muted is HISSY)

my suggestion is new tuner

technically, the capture could be stopped when the tuner is muted, and then it would be slient... but again, it goes back to how audio is managed

ie, getting from the tuner to the speakers!

**rodweb** · 05-28-2009, 05:35 AM

Sorry for being slow responding Mitch. I live on the wrong side of the world!

It seems that a post I wrote about my sources didn't make it. Sorry about that.

I am running the BMV2 skin and this DLL
http://code.google.com/p/silabsradiodll/

I see Guino's been involved in this and there is a Digital Car UK Forum thread on that site where (I think) I found a link to the BMV2 skin for it.

When I put my system together, this was the best DLL out there by far!

They talk about a line in hardware mod for Silabs on that UK thread but because my laptop does not have an AUX in, I have not gone down that path.

I suspect you are right. Silabs is pretty average. I think my way forward will be to put a head unit back in my car and either buy one of your audio switches or buy an external USB sound card with on.

I've got the head unit but I need to fit one of these as my monitor now occupies the dual DIN.

See: http://www.4wdinteriors.com/roof_console.html
Only problem is that these cost AUD $425 plus the cost to get an AUX in into my car so it is not a trivial exercise.

The other advantage of adding a head unit is that I would aslo get AM radio which is all that is available in the Australian outback.

Funny that once I select the music player, the Silabs shuts up totally! I was hoping you could mod RR to shut Silabs up on startup if the player was active.