First, keep the earbuds no more than 15m away from your phone (no obstacles). If the distance is less than 15m, follow these steps:

Topping A90 Review — Headfonics Topping A90 Review — Headfonics

Do not expose the earbuds to high or low temperatures, and do not use the earbuds during a thunderstorm. Almost all high-end phones are made of glass and metal, but for some reason the Galaxy A90 5G seems particularly slippery. The beauty of the Topping A90 headphone amplifier sound signature is that there is no sound signature. Other amplifiers have qualities that could either be described as warm, sterile, sharp, or tube-like. What you get here is what you put in basically.The Topping A90 can output a signal on both available outputs simultaneously making this amplifier versatile enough to become the centerpiece of your desktop audio setup by having the ability to drive headphones, or external amplifiers with RCA inputs or XLR connectors all at the same time with selectable inputs.

A90 Pro LED Power Display BT 5.3 Earbuds True TWS Wireless A90 Pro LED Power Display BT 5.3 Earbuds True TWS Wireless

More to the center of the rear panel are a set of identical connectors, only their functions turn into outputs and as mentioned previously, both can be used simultaneously either in fixed mode or variable depending on the front panel preamplifier switch position.

Choosing 5G over photography

The earbuds will only be charged when you correctly place them in the charging slots and close the lid.