Realtek ALC650 noise

1

First of all here’s my setup
Shuttle SN41G2
AthlonXP 2400+ 2GHz
768MB DDR RAM
Radeon 9600pro
nForce2 mobo with:
Realtek ALC650 5.1 channel audio controller (AC97 v2.2 compliant)
Realtek 8201BL Fast Ethernet network controller 10/100

The problem is the cheap sound chip - it works perfectly in Linux and Windows, but in PhOSb5 and with the Zeta 1.1 LiveCD there’s this constant noise (even when muted) as if the levels were set too high. Really annoying when using headphones :x

ich_ac97 v1.7 - works, noisy
ich_ac97 Zeta - works, noisy
ich_ac97 haiku cvs - doesn’t work - no output option in audio settings

There’s also the auich-cvs driver for intel ac97, but nothing shows… even tried the haiku mixer.media_addon to no avail :frowning:

So, any help is appreciated and I’ll avoid using my headphones for the time being :slight_smile:

2
NicePics13 wrote:
First of all here's my setup Shuttle SN41G2 AthlonXP 2400+ 2GHz 768MB DDR RAM Radeon 9600pro nForce2 mobo with: Realtek ALC650 5.1 channel audio controller (AC97 v2.2 compliant) Realtek 8201BL Fast Ethernet network controller 10/100 --- The problem is the cheap sound chip - it works perfectly in Linux and Windows, but in PhOSb5 and with the Zeta 1.1 LiveCD there's this constant noise (even when muted) as if the levels were set too high. Really annoying when using headphones :x

ich_ac97 v1.7 - works, noisy
ich_ac97 Zeta - works, noisy
ich_ac97 haiku cvs - doesn’t work - no output option in audio settings

There’s also the auich-cvs driver for intel ac97, but nothing shows… even tried the haiku mixer.media_addon to no avail :frowning:

So, any help is appreciated and I’ll avoid using my headphones for the time being :slight_smile:

I had a problem with noise on my Soundblaster Live! card, which after a long time got solved by moving the soundcard to a different PCI slot so that it didn’t have to share interrupt with USB. You could check if the sound chip shares interrupt with another device and if it does, try to move some pci cards around and see if it makes a difference…

3

:smiley: I don’t think I can as I’m running a barebone (1 PCI, 1 AGP slot)
But it seems you could be right with the IRQs - the sound chip uses IRQ 5 and shares IRQ 7 with USB 2.0. Even if I turn off Plug&Play in BIOS they end up sharing one or another.

How do I manually assign IRQs in BeOS? The only settings in my BIOS are IRQ -> PCI or IRQ -> Reserved

4
NicePics13 wrote:
:D I don't think I can as I'm running a barebone (1 PCI, 1 AGP slot) But it seems you could be right with the IRQs - the sound chip uses IRQ 5 and shares IRQ 7 with USB 2.0. Even if I turn off Plug&Play in BIOS they end up sharing one or another.

How do I manually assign IRQs in BeOS? The only settings in my BIOS are IRQ -> PCI or IRQ -> Reserved

I don’t know if it’s possible to manually assign those in BeOS, but you could try to temporarily disable the usb drivers to see if the problem is because of the IRQ sharing.

5

I disabled USB alltogether in BIOS. Still the same symptoms - not noise or static, just this hissing that’s driving me mad :lol:

---------- UPDATE --------------
I was able to lower the PCM volume with a custom AC97 mixer and get rid of the hissing. It’s not recommeded to have the PCM volume set too high (same thing with linux ALSA) :smiley: