Today I downloaded an album from HDTracks. It is 24/96 in FLAC. After the first track downloaded I was able to play it in MC. Later I tried to play the whole album and the first track refused to play. I get the message "Failed to open the file. File may be corrupt or missing." I switched the decoder to madFLAC and the file plays fine. I then downloaded and tried the file with Foobar2000 and it plays fine. I switched MC back to Automatic and the file won't play. I also converted the file to ape using madFLAC as the decoder and the file still won't play. I checked all the tags to see if something accidentally was changed but can't find anything.
The file size is 249 MB (an 11 minute song) and I decide to uncheck "Play files from memory." The song now played! Evidently since the first time I played and later I had opened many more applications and used up too much memory. I have 3 GB of memory, and the resource monitor is showing 2184 MB in use, 814 MB in standby, and 36 MB as free.
If there isn't enough memory, the file should still play as if "Play files from memory" isn't checked.