Krell Connect - USB and streaming questions

I recently purchased a used Krell Connect music server (a discontinued model) and find the sound streaming CD and lower rez 24 bit Qobuz and Tidal sounds wonderful in my full range system. It has an immediacy and full-body sound that betters my state of the art but less overbuilt devices.  (power supply and borrows from the SACD player anti-jitter as Krell site states and you hear that difference.)

The 2 questions I have (I have scoured the web and asked Krell, and a streaming service) are:

1. What format and size USB stick should I use to play back USB files, and any spec on the files? My USB stick is not being read Shows the root name but no sub-folders. I tried a ex-FAT and other options, but have not exhausted size and file/ folder structures. These files are found on a Bryston Pii (which I have sold and does sound close to this unit), PC, MAC, iFi Streamer etc...
2. Any tips to maximizing the bitrate for 24 bit feeds? Running Qobuz at 24 bit and higher than 48kHZ the playback can stop and start - all the way to stopping every 2 seconds on fullest rez files. I have a cable modem, Xfinity, wired connection through an older semi-pro model Cisco splitter in the basement. Cable is about 70-90 and 10 upload MB. Not the fastest, but reasonable.

I think my best bet is getting an answer from folks who did or still use this streamer. I am outputting to a Chord Qutest and that goes to a BAT pre and older Plinius amp to Tekton DI. As I said, I think this streamer sounds fabulous even on CD quality and slightly better rez files. I am just trying to leverage anyone else’s experience to get the most from my Subscriptions and ripped CD files.

Thanks for your time,

RyanVT