Basically this is just a fear of silence.
The fact that you don't know when a noise will startle you. The anticipation of listening to something spontaneous is what could cause the fear of silence. Also you never know if a schizophrenic person stays in a silent room he/she could begin to hear the voices much louder than they would in a noisy setting.
The closest is the fear of silence: sedatephobia.
Sedatephobia- The fear of silence; this is an irrational fear of silence.
I don't know how to get rid of it, per se, but I am working on figuring out how. I'm not sure that all fears of silence are the same. Some people fear silence in social situations, because they feel awkward, but they don't necessarily fear silence at home alone. A lot of people put on the television or radio to hear noise. I'm working on a mental mantra. Trying to say things to myself silently, while I sit in a quiet room, for two minutes a day, until I'm used to that, then three minutes and work upward. Make the jumps you feel you can make to five or ten minutes. In all honestly many people find silence uncomfortable. The biggest problem for us is saying in appropriate things, just to keep the conversation going. Sometimes this can be taken as trying to monopolize a conversation, but it's really just filling in the pauses.