The latest sales update of 1.8 million came in May, meaning the system has moved about 400,000 units since then. The PS Vita launched in February at $250.
The PS Vita will have to perform mightily if it wants to draw even with the 3DS. That system, which went on sale about a year before the PS Vita, has sold 19 million units worldwide.
Sony Worldwide Studios boss Shuhei Yoshida said last week that it is "too early" to implement a price cut for the PS Vita this year. Instead, he said he hopes software bundles like those for Little Big Planet and Call of Duty: Black Ops Declassified will steer prospective buyers toward purchases.