OK, so … first problem:
2017-11-17 21:58:03.654001+0000 BadVoltageApp[40949:50269628] App
Transport Security has blocked a cleartext HTTP (http://) resource
load since it is insecure. Temporary exceptions can be configured
via your app's Info.plist file.
Some kind soul needs to SSL the Bad Voltage site (which should have been done ages ago, to be honest) — if whoever’s doing BV sysadmin duties needs a hand with that, let me know please — or we proxy the RSS feed from somewhere that already runs over SSL.