Have a look at today's trades on DMXO if you want to see manipulation. 364*.22
A single trade at 15:21 of 9 options at 24 cents which wasn't the completion of any existing order. Then at 15:33 a trade of 364 options at 22 cents.
Total value $82.24. If you watch DMX and DMXO there are often trades like this which can push the price down a tick or two. Someone wants it lower.
I'm actually tempted to bring this to the attention of ASIC as I believe if they looked they would find it is always the same broker doing it. If proved they would be jumped on from a very great height and some of this stupidity might stop.