Honda CTX1300 Owner's Manual page 140

Symptom
About USB device
If the problem continues after the above-described inspection, have your motorcycle inspected by
your dealer.
Some USB devices may be incompatible with the audio system and/or
their operable functions may be limited.
When the audio system does not recognize the USB device connected
to the USB connector, turn the ignition switch off and then turn it on
again.
When a large number of files are stored in the USB flash drive, it
sometimes takes a long time before starting to play an audio file.
Reduce the number of files in the USB flash drive.
Check that the audio file stored in the USB flash drive is in a playable
file format. P. 47
2
Cause/remedy
Audio System Trouble
137