Can somebody trouble-shoot this test pattern?

Hi... I'm getting some serious printing problems on my Canon MX892. Only the solid black (PGBK) cartridge seems to print correctly.

Here is the nozzle test pattern. This isn't blocked nozzle(s) I'm assuming because of the regularity of the errors (and I've tried performing a deep clean).

Any ideas - does it have to go on the scrap heap?

Thanks