Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (75.81 USD): BGAFF10OFF
Coupon (75.81 USD): BGCuponation10
(CouponsFromChina.com tip: put item in your cart and apply coupon code there after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): 07cc12, 502C6B, elec, AFfbG10, BGCITYADS2019, BGE13, BGVDay10%off, bGhOnEy10, BGdragonBoat, BGSS10%SW, bgshOOp10, BgoFErTaSchInA10, BgcLuBofErtA10, 7d18f7
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Price history (for all/most countries) for FX Audio DAC-X6i Amplifier is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).