Officials said during a Friday teleconference that they want to better understand what happening and are looking at photographs and inspecting the parachutes.
"We’re not taking anything for granted," SpaceX’s William Gerstenmaier told reporters.
One of the four main parachutes was slow to inflate during the return of four astronauts to Earth in November – aboard the Dragon craft named Endeavour – and the same thing happened last week while a Dragon cargo capsule brought back International Space Station (ISS) science experiments.
The parachutes eventually opened and inflated, but with a delay of more than a minute.
The capsules safely splashed down off the Florida coast. Only three of four parachutes are necessary for a safe splashdown.
Officials noted that a similar lag also occurred during development and in previous cargo missions – potentially indicating it could just be a feature of the multiple-chute design.
Similar parachutes are also used on Boeing’s Starliner crew capsule and NASA’s Orion moon capsule – which Stich said sometimes are slow to inflate – though neither has launched astronauts yet.
Space.com reported Gerstenmaier said the issue does not present safety concerns.
"This is more of a learning exercise of how we can improve our design and engineering understanding of parachute operation," he said of the inquiry, according to the publication, telling reporters it will be a "super chance" for them to learn.
SpaceX's first private flight to the ISS is scheduled to launch from NASA's Kennedy Space Center at the end of March.
The Associated Press contributed to this report.