Not really but there are individual persons experience problem using that exchange. But the real problem of that exchange is the support they are not actively communicating with problem of user's so if you have problem you need to contact them many times.
I don't think it has to be repeated many times, it is possible that your support is in the queue and if you send it many times they will take a very long time to answer, but I have contacted the yobit about the problem I am facing, their response is quite fast, it may depend on the problem is being completed