AVsupports equipment is maintained to a professional standard; However unforeseen defects can occur, and we will do our upmost to correct the issue within reason. In the unlikely event of equipment failure and where this would have adversely affected the production, a discount may be applicable. However, the OP will not incur costs or be liable for any damages or reimbursements exceeding the rates charged for the faulty equipment.
The OP will not be liable for shortcomings in expected sound quality due to noisy environments, bad acoustics or other electrical or radio frequency related issues encountered on set.
The OP cannot be held accountable for shortcomings of or any costs related to the hiring of equipment on behalf of the client.