Verizon has touted its new unlimited data program for its mobile customers, but the carrier was reportedly putting limits on other service areas. Earlier this week, Netflix users on Verizon found that the video service was having its streaming performance limited and the carrier blamed the issue on internal testing, according to Ars Technica.

The issue first emerged when Verizon Netflix users on social media found that their video streaming was being capped at 10 Mbps. For many users, this limited performance was far lower than what Verizon’s network can typically handle. In testing with Netflix’s fast.com download speed tool on a Verizon iPhone, Ars was able to replicate the same 10 Mbps cap, despite hitting 82 Mbps on a separate app on the same phone.

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For its part, Verizon pinned the issue as being part of a temporary troubleshooting session. In a statement via The Verge, the company said it was briefly working network testing.

"We've been doing network testing over the past few days to optimize the performance of video applications on our network," Verizon said. "The testing should be completed shortly. The customer video experience was not affected."

Netflix also wasn’t the only service affected by the testing. At Howard Forums, users reported seeing a similar cap on YouTube videos. One user found that their videos were also streaming at a 10 Mbps download rate and after using a virtual private network as a workaround, they found that download performance “tripled easily.” According to Verizon, similar caps were also in place for its own streaming programs like video app Go90.

At least on most consumer smartphones, this cap isn’t necessarily a significant bottleneck for streaming performance. As Netflix notes, its 4K Ultra HD streaming requires at least 25 Mbps, but for standard HD performance — which most smartphones will stream at — it only requires a minimum download speed of 5 Mbps. At 10 Mbps, most users will be able to stream 1080p video without seeing major performance stuttering, though Howard Forums users saw some buffering with 1440p videos.

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However, the download speed cap still raises other issues around Verizon’s potential willingness to be more hands-on about its network performance. The caps aren’t necessarily a net neutrality issue — Ars Technica points out that limited performance ceilings can be put into place if they’re not restricted to specific services.

But Verizon has previously said that it wouldn’t tamper or place any limits on what content providers like Netflix or Youtube provide to Verizon customers. With the increasing attention paid towards net neutrality and the Federal Communications Commission’s potential repeal of these rules, the networks of Verizon and other telecom companies will likely be under similarly increased scrutiny.