A Possible Solution to Eliminating RF and EMI Noise When Using a DAC with an iPhone 14 or 15 Pro Max

I've bought and returned many DACs with the hopes of using them with the iPhone 14 Pro Max, and now the 15 Pro Max. The DACs I have tried were the Questyle M15, Cayin RU7, Shanling UA5, iBasso DC04Pro, and DC06Pro, and was always the same - RF interference ruining the experience. These DACs just don't have enough shielding to block the unwanted electromagnetic waves.

Today, I ordered and received (same day free shipping and a $100 instant rebate) the Questyle M15i from Amazon. This DAC is touted as being made for iPhones and iPads - it even says so right on the packaging! Hopeful, I tried it with the iPhone 15 Pro Max, and sure enough, static, buzz, crackle. Didn't matter the USB cord, the distance from the iPhone, etc. Frustrated, but not surprised I tried various settings that for whatever reason, didn't occur to me before. Finally, I found a solution!!!

First, go into Settings, then Bluetooth, and turn that switch to off!

Second, turn on Airplane mode.

Third and finally, manually turn on the wifi. Notice the top left shows the cellular and bluetooth completely turned off.

I can't speak for every DAC, but at least in my testing, the M15i works just fine with the aforementioned settings.

Send me a message and let me know if this works for you.