A Shoutcast process (called sc_serv25, with PID 10213) is using way more CPU than expected for the workload - specifically, 100% of a CPU core. Let's investigate.
$ sudo strace -p 10213 -o ~/sc_serv25_strace.txt -f -t -tt -T
(control-c after a few seconds)
Looking at sc_serv25_strace.txt for weirdness, we notice thread 10221 is very hot. Here's an excerpt:
$ grep 10221 ~/sc_serv25_strace.txt
...
10221 1499065013.244010 poll([{fd=14, events=POLLIN}, {fd=75, events=POLLIN}], 2, 0) = 0 (Timeout) <0.000009>