I've run into a problem with my Alphasim S-55 installation. For some reason I've lost all engine sound and have only the touchdown sound remaining. To save space I've aliased the sound in the aircraft folder to a "Sounds" folder in the "Aircraft" file. This worked fine until today. I've made sure my speakers and headphones are working. Sounds for other aircraft work fine. I've tried other engine sounds in the alias folder, as well as installing them directly into the S-55 aircraft folder as an experiment to see if the sim can read them directly. I've also made sure the engine type in the S-55 aircraft cfg file matches what is in the S-55 sound config file. None of those measures works. Has anyone ever run into something like this before?