The Nikkei said Foxconn and Pegatron were asked to halt the new production capacity, with the former producing 100,000 fewer units each day than first anticipated in its Taiwan-based facility. Pegatron is also holding back on adding extra production lines until it gets more clarity on XR demand from Apple, the Nikkei reported, without saying where it got the information. The reports followed a decision by Apple to no longer provide detailed numbers for the sale of it individual products, such as iPhones and mac computers, meaning investors will no longer be able to calculate their average selling price, a key metric used to gauge the company's profitability.

The decision to scrap that guidance, as well as forecasts for December quarter sales of around $91 billion over the three months ending in December, overshadowed a stronger-than-expected September quarter which saw better-than-expected earnings of $2.91 per share and group revenues of $62.9 billion, and sent shares tumbling more than 6.3% Friday, the biggest single-day decline since 2014.

"The lack of transparency is disappointing, and will likely limit investor's visibility into the company," said BMO Capital Markets's Tim Long. "Our view remains that units may not grow at all going forward, and while (Average Selling Prices) are still increasing, at some point they will plateau."

Apple shares were marked 4.3% lower in the opening hour of trading Monday and changing hands at $198.54 each, the lowest since July 31 and a move that would still leave it with a year-to-date advance of around 18%, but extend its quarterly loss to around 13% and value the Cupertino, Calif.-based group at under $950 billion.

Apple launched the 6.1 inch LCD version of its iPhone, the XR, at around $750 in early September as a lower-priced alternative to the more expensive iPhone XS, the XS Max, which start at $1,000 and $1,100 respectively.

"While we don't expect the new lineup to drive unit volume growth to the levels seen during the iPhone 6 cycle, due to a mature smartphone market, revenues should still see a very healthy jump due to a continued uptick in average selling prices, with mid-range iPhone customers likely to upgrade to the XR and premium buyers likely opting for the new iPhone XS Max (top models cost $1,450)," said analysts at Trefis.

Apple said it shifted 46.9 million iPhones over the three months ending in September, a figure that was largely in-line with analysts' forecasts but was flattered by a much stronger-than-expected average selling price of $793, which topped the $751 consensus and rose 28.3% from the same period last year.

Services revenue, which includes App Store, Apple Music, iCloud Storage and Apple Pay sales, rose 27% to $10 billion but slowed from the 31% recorded in the June quarter, an easing that may have been affected by the slower pace of iPhones sales that reduces the so-called installed base.