This bug has happened to me for three separate PoE bounties now over the past two days. Counter goes down by approx. 3% every tick and there are next to no enemies spawning. I agree that the size of the bounty area needs to be made much smaller because this is near impossible to do solo now, especially on the higher bounty stages. Edit: Forgot to mention that this does not happen all the time. Sometimes the bounty goes smoothly and other times it does not, so I find it difficult to pinpoint when and where it happens.