We have listed many common concerns that customers may have, and you can check here to see if they can solve the problem. Before contacting us, reading here can help you solve the problem more quickly.

Product warranty​

1. Earphones : one-year limited manufacturer’s warranty for both earphones and earphone cable; other accessories including the silicone eartips, carry case are not covered by warranty.
2. Cables: one-year limited manufacturer’s warranty
3. DAC and AMP: : one-year limited manufacturer’s warranty
4. Adapter: : one-year limited manufacturer’s warranty
5. Carrying case, earphone case and earphone cable clip: no warranty

Please kindly be noted that you could return the item within 15 days after receiving, if your products are purchased from our official AliExpress store, except for the customized products.

1). Please contact us at support@ddhifi.com with detailed info about the product problem for further analysis firstly.

2). Please also provide the purchase receipt for this product.

Meanwhile, if you buy DD products from local sales agents, please refer to them regarding the warranty terms that set based on local rules and regulations.

DAC dongle TC35B

A: It’s tested to be compatible with various of Type-C smartphone from brands such as Samsung, Xiaomi, Oppo, Vivo, Meizu, Huawei, etc. All the phones have no issue in playing music, but some of them don’t support in-line control volume adjustment.

A: If you find the in-line control volume adjustment invalid or other issues, it’s suggested to take out the earphone and use the microphone to answer your phone call. Since the line control function of phone differs from brand to brand, and some phones have special specifications for accessory agreement, so that it may make them not compatible that perfectly.

A: The Type-C interface on the phone would have gone through dozens of high-strength tests during the production, and the force of using the adapter is almost the same as that of using the charging cable. So if use properly, there is no need to worry about damage.

Headphone Adapter DJ44B/DJ44C

A: The 4.4mm socket is much bigger than the 2.5mm socket, if we still use transparent plastic housing, the wall thickness should be thicker as well, eg, the minimum required thickness is 0.4mm if use stainless steel, but would be 1mm if use plastic, which would be hard to make it as small and compact as possible. In order to make it solid as well as compact, we use the more expensive 316 stainless steel as its material.

A: For the DJ44B/DJ44C, we use high purity 6N OCC for internal wiring, high fidelity soldering tin for the soldering, and high quality gold-plated layer for the socket and plug. All of these make sure the transmitting signal is reliable enough, so as to guarantee the sound quality is as lossless as possible.

A: This is caused by the increased cost on the product processing and high quality materials. The housing and the cover are all metal and they are all processed by CNC-ed machining. One thing that needs to be mentioned is the cutting tool requires to change to a new one after processed tens of stainless steel products. In order to provide better user experience, the cost is correspondingly higher.

A: We’ve been asked this question before. This adapter is a dedicated accessory for earphones by switching between different plugs, it’s not a mini speaker or others.

Headphone Adapter DJ35A/DJ44A

A: The 2.5mm output is balanced signal, if we transform the 2.5mm male to 3.5mm female, we need to short out the two negative poles of the balanced output, which will possibly damage the output device, so it’s not suggested to use in this way.

A: There are many factors that may affect the sound quality, but for an adapter, the determining factor is the gold-plated layer. For all the DJ series products, we use high quality copper with thick galvanized gold-plated layer, to make sure it has good electrical property with the connecting points on the female jack. What’s more, the FPCB connection is very short, which has very limited effect to the sound quality.

A: The connection on the 2.5mm female side may be a little bit tight, so please make sure the earphone is well plugged in.

TC35i (2021) Lightning to 3.5mm Aapter

A: It uses MFi certified Lightning chip and connector, so you are rest assured that there will be no compatibility issue. But owing to some restrictions, the TC35i, as well as other third-party earphone-related finished products, is unable to get the MFi certification.

A: It supports all the functions of Apple headset, including in-line controls and microphone; it supports most of the functions of CTIA standard earphones, including play/pause and answering phone call, but can’t adjust volume.

A: 1). The TC35i uses official connector and chip, the audio signal will only go through the decoding and amplification. 2). Owing to the cable-free design, it can largely reduce the influence to sound quality. 3). The all-metal shell can more effectively shield electromagnetic interference and further ensure the lossless transmission of sound quality. So it‘s supposed to have an overall better sound quality than the Apple official adapter.

A: The audio output for iSO products are commonly fixed. When using the TC35i, the sampling rates is 48KHz. Sorry that there are no other detailed data can be shared.