Apple's problematic $349 HomePod speaker has already sold out before launch. Pre-sales of the smart device have apparently been brisk enough, that delivery is being pushed back until next week, with pick-up options not even available when the product officially goes on sale February 9.

Demand for Apple products are traditionally high. Customers are known to set alarms to place the first order for a new Apple devices, like the iPhone X, with items selling out within hours.

In the case of HomePod, however, Apple's stock of the device is unknown — and may be low. Initial demand also can't predict future sales. While the iPhone X saw huge pre-orders on its first day, customers have been slow to adopt the smartphone. Apple actually has had to retool its sales estimates.

HomePod, a speaker that runs through Apple's voice assistant Siri, is meeting mixed reviews. While there's almost universal excitement about its sound quality, that has not carried to its function as a smart home hub. The device can't make phone calls, can't pull up recipes (an Alexa favorite) and doesn't work as well with Siri as the iPhone. Some complaints seemed a bit over-reaching such as not being able to use Spotify and other music programs with HomePod. They can be used with a bit of AirPlay alchemy.

But while originally touted as a weighty competitor to the Amazon Echo and Google Home products, HomePod's true worth to the smart home is not known yet.