Humming during shmoneh esre
Is saying "oyoyoy" in places where you're not allowed to speak (e.g. Shemoneh Esreh) a hefsek (interruption)? Does it make a difference that it doesn't have any consonant sounds (in which case "oyoyoy" would be permitted and "aididididi" forbidden)?
Related: Hefsek (interruption) between the blessing on food and eating the food, but there the problem is that you distract your mind from the bread (MB 166:1) while here you aren't allowed to talk even if you don't distract your mind.