A dip in sound quality could potentially be a hardware or setup issue. But if everything seemed fine and then suddenly isn’t, then the cause is more likely Prime Video itself. As originally spotted by 4KFilme, then later confirmed with The Verge by an Amazon spokesperson, it has to do with your particular subscription plan.
Prime Video currently offers a choice between four possible subscription tiers: Included with a regular Prime subscription ($14.99 per month or $139 per year), on its own ($8.99 per month), ad-free with Prime ($17.98 per month), or ad-free on its own ($11.98 per month). What matters here is whether or not you’re using Prime Video with ads. Amazon spokesperson Katie Barker told The Verge that support for both Dolby Vision and Dolby Atmos, which together form Dolby Cinema, are only included (for relevant titles) with one of the ad-free subscription plans. That means that the only way for you to get your Prime streaming sound quality back up to where it used to be is to upgrade and pay about $3 more every month.
If you want Dolby support without the increased price, you don’t have many other options. Several other streaming services do support it, but out of all of them, Apple TV+ ($9.99 per month) is the only one that comes in below ad-free Prime’s $11.98 per month. Max, Netflix, Disney+, and Paramount+ all require subscribing to their more costly services.
