
Irish Broadband entered a contract with you, to make a contract binding both parties must comply with the terms of the contract. You must document your efforts to rectify the problem with Irish Broadband. Log your calls to them, save your emails from/to them. Irish consumer law (or protection for the consumer) is weak, so you also have to give them a reasonable amount of time to rectify the problem. After that you can cancel your Direct Debit, then call or email cancelling your arangement with them and tell them to remove the equipment. They won't bring you to court, they would not have a case.
I am in Ennis, I had the same problem with them, the download speeds have improved dramatically, not 1mb but 500 to 800kb. The uploads are still 100 to 200kb. It is the only wireless provider here. As soon as another appears, I reckon a lot of "rats will jump ship"