This might be of use:
Asambhinnattā sotassa, āpāthagatattā saddānaṃ, ākāsasannissitaṃ, manasikārahetukaṃ catūhi paccayehi uppajjati sotaviññāṇaṃ, saddhiṃ sampayuttadhammehi.
Ear-consciousness arises with its concomitant mental factors by four conditions: the unimpaired state of the ear, the coming of sounds into range, dependence on space (ākāsa), and being caused by attention (manasikāra).
Dhammasaṅgaṇīaṭṭhakathā p. 322