Tech giant Samsung Electronics said Wednesday shipments of the Galaxy Note 7 smartphone are being delayed as the firm conducts additional quality control testing for the premium device.
Samsung did not elaborate what it is testing and to what markets shipments are being delayed.
Local media reports have said some users of the Galaxy Note 7, which launched in South Korea and other markets earlier this month, have claimed that the battery for their phones exploded.
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Quality control problems, if confirmed, could deal a major blow to the world’s top smartphone maker as the firm is counting on the sales of the new device to maintain sales momentum for the mobile business in the second half of this year.
Samsung (ssnlf) has previously said demand for the new Galaxy Note phone is far exceeding production, creating a supply shortage and forcing it to push back the launch of the phone in some markets. The firm has said it is utilizing all possible means to boost production.
Production problems for the curved displays for the Galaxy S6 edge phone resulted in disappointing sales last year, and some investors fear a repeat if Samsung does not move quickly to meet Note 7 demand.
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The Galaxy Note 7 retails in South Korea for 988,900 won ($887.63) without subsidies.
Samsung’s other premium smartphone models that launched in March, the Galaxy S7 and S7 edge, have been huge hits with customers and helped boost its earnings in the first half of 2016.