We refer to Jake van der Kamp's 'Monitor' column headlined 'Cacophony cripples commuting' (South China Morning Post Business, April 3), as well as letters which have appeared in these columns regarding the multimedia-on-board (MMOB) system on our buses. We are fully aware of our customers' comments, and we have also found the noise levels on a few buses still require further adjustment. We understand their frustrations, and we are, as quickly as possible, tuning the equipment on all buses fitted with MMOB to a more agreeable level of sound. We trust that when we have achieved this, our customers will find their journeys to be a more tolerable experience. We have frequently been asked by customers why we are equipping our buses with this system. To put it bluntly, we are maximising every possible opportunity to generate additional revenue so that we can delay, for as long as possible, the day when Citybus has to raise fares. We last increased fares in December 1997, and since then, our fuel bill has shot up by more than 80 per cent, a sum we have totally absorbed and not passed on to the travelling public. In the past two years, we have frozen wages, but we doubt if we can resist the demands of staff this year. We are exceedingly mindful of the social consequences of an increase in fares, and this is why we have to seek every opportunity to avoid this for as long as we can. We hope our customers will understand this and bear with us. CHRISTINE LAU Corporate Communications Manager Citybus Limited