Constant Crashes .... com.apple.NSEventThread

I had a session today for a film score and had multiple crashes at random.

The crash reporter gave me this...

Process: MainStage 3 [748]

Path: /Applications/MainStage 3.app/Contents/MacOS/MainStage 3

Identifier: com.apple.mainstage3

Version: 3.2.4 (4300.44)

Build Info: MAMainStage-4300044000000000~1

App Item ID: 634159523

App External ID: 816296074

Code Type: X86-64 (Native)

Parent Process: ??? [1]

Responsible: MainStage 3 [748]

User ID: 501

Date/Time: 2016-06-15 20:52:17.909 -0700

OS Version: Mac OS X 10.11.5 (15F34)

Report Version: 11

Time Awake Since Boot: 33000 seconds

System Integrity Protection: enabled

Crashed Thread: 26 com.apple.NSEventThread

Exception Type: EXC_BREAKPOINT (SIGTRAP)

Exception Codes: 0x0000000000000002, 0x0000000000000000

Exception Note: EXC_CORPSE_NOTIFY

Thread 26 Crashed:: com.apple.NSEventThread

0 com.apple.CoreFoundation 0x00007fff875b12a7 __CFRunLoopServiceMachPort + 439

1 com.apple.CoreFoundation 0x00007fff875b068c __CFRunLoopRun + 1356

2 com.apple.CoreFoundation 0x00007fff875afed8 CFRunLoopRunSpecific + 296

3 com.apple.AppKit 0x00007fff880d6d95 _NSEventThread + 149

4 libsystem_pthread.dylib 0x00007fff8dbdb99d _pthread_body + 131

5 libsystem_pthread.dylib 0x00007fff8dbdb91a _pthread_start + 168

6 libsystem_pthread.dylib 0x00007fff8dbd9351 thread_start + 13

I'm not sure whats causing this. Anyone help out?