ssh over wlan / wifi connection problems

Connecting in local wireless network at home (wpa2 with key) from my windows pc to my Jolla with ssh putty (TCP keepalive set on). First connection doesn't work, I can't see the Jolla from my pc, until I initiate some pings from the Jolla to the pc. Then I am able to 'see' the Jolla from my pc and connect through ssh. Once connected to the Jolla, I lose the connection quite easily again, after some inactivity, the Jolla is again invisible from the pc. Is this a common problem of Jollas wlan implementation, maybe some timeout? Any workaround? I don't have this problem with other wireless connected devices (android, raspberry and others). Any hint greatly appreciated.