Weird connection issue, finally come to solution
 

Right I usually switch my cable modem off when i go to bed, (pc is in room, just turn switch off from wall) and if i turn the modem back on and wait for it to connect then use the net i experience packet loss and random high ping times.

However, if i leave my pc off (no internet usage) and leave the modem on when i'm in school, by the time I come home and use the net everything is fine (no packet loss, great pings).

What causes this?