At this time each Roku account can only be associated with one Pandora account, so you won't be able to use multiple Pandora accounts on a single Roku device. If you want to listen to two different Pandora accounts, you'll need:
two Roku devices
two Roku accounts (one on each).
If you have more than one Roku device and have already signed them into the same Roku account, you can manage your devices using the following steps:
Go to my.roku.com on your computer or smartphone.
If you are not already logged in, sign in to your Roku account.
Scroll down to the bottom of the My account page and locate the device under the My linked devices section.
Select Unlink on the correct device, and confirm your choice.
Then you can associate that Roku device with a new Roku account (and thereafter, with a new Pandora account). If you need to, you can create a Roku account here.
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