Why it matters: Last week brought news that Netflix would soon stop working on some older Samsung and Vizio TVs, as well as certain Roku devices. The streaming service didn’t specify why this was happening, but now we know the reason.

Netflix had said that the affected devices are no longer supported due to “technical limitations,” which isn’t much of an explanation.

Now, a Netflix spokesperson (via Gizmodo) has given more details: it’s all to do with DRM. With regards to the older Roku devices, these are running Windows Media DRM, but Netflix has been using Microsoft PlayReady since 2010. So, as of December 2, these older products that can’t be upgraded to PlayReady will no longer be supported by Netflix.

The Roku devices in question are between eight and ten years old. They include Roku SD (N1050), Roku HD-XR (N1101), Roku HD (N1100, 2000C), and Roku XD (2050X, 2050N, 2100X, 2100N). If you’re still using one of these, you should probably upgrade before losing the service.

Additionally, Netflix said the change would also “impact select 2010 and 2011 Samsung Smart TV models that were sold in the U.S. and Canada.”

For Vizio TV owners, the affected devices were sold around 2012 to 2014 and include some of its Smart TVs with VIZIO Internet Apps (V.I.A.). The company did say that Netflix “continues to work smoothly on other VIZIO Smart TVs with VIZIO Internet Apps Plus (V.I.A. Plus) and SmartCast TVs/Displays. There are still over 70 apps available to consumers with V.I.A. devices.”

While Gizmodo didn’t reveal if Netflix dropping support for older Samsung and Vizio TVs was also related to Windows Media DRM, this is likely to be the case.