A temporary workaround is to use "Google Home", select the device you normally chromecast to, and select "Play all audio on this device". Then launch Poweramp. But the sound is really poor quality compared to regular chromecast. Hope it's fixed rapidly.
Can't ChromeCast from Poweramp
in Poweramp Bug Reports
Posted
Same issue here.
A temporary workaround is to use "Google Home", select the device you normally chromecast to, and select "Play all audio on this device". Then launch Poweramp. But the sound is really poor quality compared to regular chromecast. Hope it's fixed rapidly.