Hmm...that's interesting. glad to hear it's okay now. It doesn't sound like a hardware problem to me. If it keeps happening, maybe try reinstalling the system. Remember to backup before you do the restore tho
P.S you might want to avoid sony Pc companion for backup. It failed to restore last time I tried and a lot of people reported that the app would freeze for quite a while (in some cases stayed frozen forever) if your backup is big.
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