Background: Last week, telecom lobbying association COAI said in a letter to TRAI that a manufacturing glitch in MediaTek chipsets affected service quality offered by telcos. The issue was apparently widespread in dual SIM devices: whenever a 4G SIM is placed in the secondary slot, flow of data gets affected since the secondary slot is meant for a 2G SIM only, COAI claimed.

Although MediaTek initially said that it was working on fixing the issue, it has now put out a divergent statement: “It has been inaccurately reported that this dual-SIM issue is only apparent in MediaTek powered phones,” MediaTek said. It also agreed to the fact that the issue was present in chipsets it manufactures but added that “the reduced data rate is not necessarily noticeable to users.”

The chipset maker also pointed out that “half of the eight devices that COAI cited as causing network degradation, are powered by other chipset makers or competitors to MediaTek”. The company added that it was able to confirm the “networking slowing effect” after conducting its own set of tests on non-MediaTek mobile phones. COAI had claimed that the glitch “significantly deteriorates throughput of any other operator’s 4G SIM…by as much as 40%.”

‘We have designed a solution for the glitch’: MediaTek

The chipset maker also said that it has developed a software-based optimization method to improve network performance on dual-SIM phones. This is now being tested with mobile operators, according to its statement. “Once the solution is fully tested and approved – expected in the upcoming days – it will be shared with customers to resolve network concerns,” MediaTek added.

Note that COAI also requested government intervention for fixing the issue. It had urged authorities to mandate an Over The Air update within 4 weeks time to fix the issue, or else these manufacturers should withdraw all their phones from the market.

 MediaTek says dual-SIM issue is limited to India

Apart from this, MediaTek claimed that the dual-SIM issue is “limited to India”, mostly due to a lack of uniform network standard among multiple mobile operators in the country. “Currently there is no single standard in India for dual-SIM devices and no over-arching requirement under the 3GPP standards – which MediaTek complies with,” the chipset maker said.

According to the chipset maker, telecom service providers usually share their own SIM card requirements with chipset makers before they roll-out their networks. But in India, “SIM requirements across 2G, 3G, 4G and 4G-LTE networks have led to some unintentional compatibility challenges for the industry to address,” the company added.