I just upgraded to Ubuntu 12.04 from a disc from Linux Format magazine. It was an LXF Remix, with Unity and XFCE on it. It loaded fine, and I have access to either Unity or XFCE.

My problem is that when I put audio into the microphone jack, it starts coming out of the speakers! This never happened with previous versions of Ubuntu (9.10 or 10.10). I dual boot with Windows XP, and I don't have that problem with XP. I also run ham radio software via Ubuntu/Xubuntu which this plays havoc with, and I can't shut off the speakers or headphones when running this software, since they are needed.

This is a 2003 vintage Dell Inspiron 1100 with an Intel 82801 DB-ICH4 sound card (Sigmatel audio).