I replaced the PCI SBlive 5:1 with another lesser PCI SB card, which was not correctly identified by the machine. After rebooting the AlsaMixer gave me a different chip-set which was incorrect also.
Now, I appreciate that I could have given a better description initially for the hardware situation here. I use 2 sound cards, an onboard Realtek ALC 850 & the SBlive, which had stopped working long enough ago for me to just kind of forget it even existed, BUT it was still in the machine.
I currently have removed PCI sound & after a couple of reboots, AlsaMixer is seeing the correct chip-set & working.
I think that the problem has been caused by confusion over which sound chip to use, the onboard one that works & is wired up, & the other which doesn't as is not wired.
I expect to that if there is anymore sound failure's if I look at AlsaMixer that a non-existant chip-set has been allocated the sound handling for the system.
Hopefully with only the onboard sound existing in the machine now, I won't have anymore problems.
Still, it was interesting when this first started happening that Cedega did not work, & all else did?!
Ok, I think I understand what happened with Cedega, when it initialised the Alsa sound for itself it chose the wrong card, easy.
Ex Arch user (4.5 years), on the run from the Systemd Virus. Feeling relatively safe here for the time being...