Continue meditating as with any kind of a distraction. When you become aware that you are distracted, note it, come back, note it, come back. Allow it to stay in the background if you can. Another example of this is, you are sitting in the hall, it is all quiet, the birds start singing. It may distract you - note it and come back. If they keep singing for 20 minutes, most of you could probably not care less. It stays in the background, you know it is there, but you go back to your meditation subject. Try to treat the ringing of the bell, the hearing of the bell the same way.
Now the bell is much louder than the birds singing. So if it is distracting your mind so often, and you have noted "hearing, hearing" and come back so many times and you think, "oh this is overpowering", fine, change your subject of meditation. You can treat it in a way of listening and just "hearing, hearing" and be aware of the tones and the movements, or you can go into reflection on impermanence, see the changing nature of the sound, that is fine. So, to a certain extent, all you are going to do is to treat it very similarly to any other distraction that you can have in your practice. It is just another one.