I'm not familiar with this software, but it looks like it supports some sort of plugins and/or scripts that extend its basic functionality.
It looks like someone made a mistake when writing a program, script, or structured configuration file that "Beat" wants to use. I do not know what the specific mistake is, but the program that was reading the bad file saw a '.' character where it did not expect to see one, and rejected the input as faulty.
For instance, here is a C program with a deliberate error (the '.' after "printf").
#include <stdio.h>
int main()
{
printf.("Hello, world!\n");
return 0;
}
When I try to compile this program, the compiler chokes on the '.' and throws out an error. It did not use the term 'SyntaxError', but "syntax error" is the generic name for this type of error.
% cc -o syntax syntax.c
syntax.c:5:12: error: expected identifier
printf.("Hello, world!\n");
^
1 error generated.
The syntax error is not, in and of itself, an indication that the program contains malware or viruses. It is an indication that whatever feature or extension you are trying to use may not work properly until the underlying issue is fixed.
I would suggest checking with the "Beat" developers, and/or the developers of any plug-ins you may have installed, to get to the bottom of that.