If a customer has an issue with a rental item from Guitar Center, they should first ensure that they have reviewed the rental agreement and rental policies, as these contain important information about the procedures to follow in such cases. The customer should examine the condition of the item, note any damage, malfunction, or concerns, and take detailed notes regarding the issue. If the problem is not easily resolvable, such as a simple user error, the next step is to visit the current location of Guitar Center where the rental occurred. It is beneficial to bring the rental item and any relevant documentation, including the receipt and rental agreement, to facilitate a smooth discussion. The employees at Guitar Center are experienced and can provide guidance on the resolution process. For any specific inquiries or further assistance, it is advisable to look on the Guitar Center website, where contact information for customer support is readily available.