Cr-H258i Cd Receiver,working ok,iPod touch,working fine, Teac DS 22 dock,less than month old, has worked, but now keeps coming up as 'not connected' on the stereo display. Tried reconnecting iPod and/or dock many times but don't know what else to try. [the connections seem fine ,and stereo and iPod work o.k. on their own]

The DS22 is nothing more than a data cable with a case around one of its end plus a simple set of extra connectors - no electronics whatsoever.
If the dock is detected as unconnected then either the cable that it uses to connect to the main unit has broken a wire internally or the connector itself (the one to the device) has one of the pins detached. Since both defects are unfixable - the cable can't be spliced to repair the breakage and the pins can't be resoldered - it means that the dock is dead and you will have to buy a new one.
Luckily it's not a very expensive item, it won't cost you much to replace it.