Ahh what a bummer, looks like the 500 driver is MASSIVELY crippled compared to the older POD XT drivers and the toneport drivers.
Line6 seriously, what's with all the backwards steps? The Firehawk and Amplifi have worse drivers in every single way than the older drivers. I'm getting to the point where I am about to remove Line 6 products from my FAQ's and recommendations.
raiyanhrid. OK, so as silverhead said, just make a dry patch
Turn "hardware monitoring" off, all the way to the left on your "inputs and recording" tab of the line 6 driver control panel
Ad a track in REAPER, arm it, set it to input 1, and turn on the monitor icon for that track.
Unless Line 6 COMPLETELY blew it on this driver and actually stepped back more than a decade (which at this point, and man, I'm really, really disturbed by this, wouldn't actually surprise me), this should work out perfectly