A method of inkjet printing includes the steps of: (i) delivering ink to a printhead manifold having a longitudinal ink channel, one or printhead chips mounted to a floor of the printhead manifold and in fluid communication with the longitudinal ink channel, and a plurality of sealed air cavities positioned over the longitudinal ink channel for dampening pressure fluctuations in the ink; (ii) printing from the printhead chips; and (iii) replenishing the air cavities with air.