This morning I was awake early, before the people next door.
The people next door turn off their router at night. This morning the my HOS connected to my router, the SSID is still hidden. I confirmed with Wifi-Analyzer that next door had turned off their router which is always broadcasting 3 SSID values all on Channel 1 which is standard behaviour for BT HomeHub routers these days.
Later in the morning I could hear people next door, I power cycled Wifi on the HOS, and now it will not connect to my router. My router is on Channel 7.
This is the only HTC Android phone I have had which has had this problem, my other Android devices never had a problem.
HTC 1S, Nexus 7 and Galaxy S3mini.
Asus TF101 with Random Reboots