I have now belatedly seen this thread
which describes the same problem.
I have found that this is an intermittent problem. There is no obvious correlation with anything of the settings. Most times a reboot comes back with good sound, sometimes there is a problem. I have now set up runeaudio to work as a volume control and set up the inputs and outputs using alsamixer rather than scripts
My suspicion is that it is to do with the order of powering up the various components: TV, DAC, Cirrus but I have no evidence!!