Over the last 10+ years many companies in the United States have been switching to using a third-party to respond to background checks for jobs and loans.
In the case of background checks for jobs, the service provides dates of employment, job title, and little else. This is done to eliminate any need to provide any detailed performance information. This minimizes their risk of getting sued by a former employee because of a bad reference check. It also protects employees because the new company won't be talking to their current boss.
In the case of a employment check to approve a loan, the companies only release pay information if the employee has told the 3rd party company that bank x will be contacting them. This is generally done by getting a pin or reference number for the bank to use when requesting the pay information.
When I have called references during the hiring process I have not been interested in the performance information from their current manager. They are biased. They want to keep good employees and get rid of poor employees. Plus it jeopardizes the candidates current job situation.
Find out if your current employer uses a external company for this information.