How close to the wifi access point is the S1 ?
To be honest the S1 isn't great at wifi, and mine used to do that, id have to drag their sorry arses out of the cupboard and bring them back to the access point to re aquire the signal and then put them back, in the end i got a 15 mtr ethernet cable and hard wired them.
Well when I configure the miner settings it says that the connection is 30-40%, but after I apply the settings it says 0%