JRiver's 'Remote Control - Commands' need to be refreshed on each computer restart. See link below for further details.
Honestly, I'm not sure if this post should be in
JRiver 33 forum, here, or where I originally posted it in
Remotes forum... but since it seems to be a glitch I'm currently experiencing in JRiver 33, I thought to post it here. Details here:
https://yabb.jriver.com/interact/index.php/topic,139736.msg968919.html#msg968919