Acer 2492 laptop - Poor quality sound / sound mixer not working properly

Has anyone else had problems with the sound on an Acer Travelmate 2492 WLMi
laptop with Realtek HD audio?

My new laptop is excellent in every respect except the sound which is
causing me problems:

First of all, although the sound from the line in records perfectly well,
the mike input is very noisy and instant messenger and chat programs such as
Paltalk or MSN have appalling sound quality - very distorted and mushy. This
is evident even in local "sound test" menus, and so is not a
networking/internet issue - it's to do with the feed of data from the sound
card to Paltalk etc.

Secondly, at a random time after talking on Paltalk, the "Stereo mix" input
to the recording mixer stops working. Normally anything that can be heard
through the speakers (wave, mike etc) becomes available to be recorded or to
be output through Paltalk or MSN Messenger. However this input often
suddenly fails: even though sound can be heard, it is no longer recordable.
Mike and line-in inputs still work fine. Only a reboot cures the problem.

I've just tried updating the drivers to the latest version (1.54 rather than
1.41 which is what is supplied with the PC) and this cures some problems but
creates other new ones

With the 1.41 set (listed in Device Manager as 5.10.00.5273):

- the mixer intermittently loses the Stereo Mix input and the CD input on
the Recording volume control: you can select them but nothing is recorded;
line-in and mic still work

- the mike, as heard live through the headphones, only plays through the
left channel; however it records on both channels (in mono)

With the 1.54 set (listed in Device Manager as 5.10.00.5345):

- the mixer always fails to record from Stereo Mix or CD

- the mike plays through both channels and records in stereo (although I
only have a mono mike, I've proved this by connecting an external lead and
touching first the left then the right pin of the phonos at the far end of
the lead!)

In both cases, the mike signal is *very* noisy: having recorded the
"silence" in CoolEdit, it looks like pink noise - louder at lower
frequencies than at high frequencies. With either the internal or an
external mike, I'm getting noise at about -24 dB with sound peaking at
about -6 dB, so signal-to-noise of only 18 dB. Turning mike boost on and off
only affects the overall volume - the ratio of signal to noise stays about
the same.

Sadly, Realtek's site only has the 1.54 drivers, both as offered on the web
page and by looking behind the scenes on the FTP site, so I can't try other
builds of the drivers between 1.41 and 1.54




.