<span style="font-family: courier new,monospace;">You have tried the settings in alsamixer, as Raoul suggested</span><span style="font-family: courier new,monospace;">? <br><br> *-multimedia</span><br style="font-family: courier new,monospace;">
<span style="font-family: courier new,monospace;">
description: Audio device</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">
product: <span style="background-color: rgb(255, 255, 102); color: rgb(0, 0, 0);">82801H </span>(ICH8 Family) HD Audio Controller</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">
vendor: Intel Corporation</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">
physical id: 1b</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">
bus info: pci@0000:00:1b.0</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">
version: 02</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">
width: 64 bits</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">
clock: 33MHz</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">
capabilities: bus_master cap_list</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">
configuration: driver=HDA Intel latency=0</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">
resources: irq:22 memory:90320000-90323fff</span><br style="font-family: courier new,monospace;"><br style="font-family: courier new,monospace;">Googling "ubuntu 10.04 82801H sound issue" gives a couple results, <a href="https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/411574">this Launchpad Bug</a> (for Karmic), which explains why it worked for you in 8.04 before Karmic. There are a good couple of posts of things you can try, most involve just tweaking settings. <br>
<br>Also there is this more <a href="https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/572063">recently logged bug</a>, same issue for Lucid. Login to Launchpad and click the "Does this bug affect you" link. <br>