If you are not able to get the timeshift working on your Amiko follow the next steps.
This is under Spark platform
Plugin USB HDD or stick, preferable on EXT3
Press the following sequence “Main Menu/ USB/ PVR Setting/Time Shift”
Turn timeshift on
If you set it on 30 min it will work fine if writing speed of your usb device is high. If you go beyond like 60 min etc it can give some hickups in playback.
To activate timesshift , press the timeshift key first before pressing record!