Polyphase Dispatcher - NPE On Shutdown

[DSheirer]

sdrtrunk Version
Version 0.6.0 Alpha 5

Describe the bug

As reported by user:

I'm seeing this on Windows V6 A5.

2023-04-12 14:43:28.619 INFO  i.g.d.d.f.c.ComplexPolyphaseChannelizerM2 - Sample Rate [2500000.0] providing [100] channels at [25000.0] Hz each  [138MB/260MB 53%]
2023-04-12 14:43:28.642 INFO  i.g.d.d.f.c.ComplexPolyphaseChannelizerM2 - Sample Rate [2500000.0] providing [100] channels at [25000.0] Hz each  [145MB/260MB 55%]
2023-04-12 14:43:28.751 INFO  i.g.d.a.c.m.AmbeAudioModule - AMBE CODEC successfully loaded - P25-2/DMR/NXDN audio will be available  [161MB/260MB 62%]
2023-04-12 14:43:28.777 INFO  i.g.d.d.f.c.ComplexPolyphaseChannelizerM2 - Sample Rate [2400000.0] providing [96] channels at [25000.0] Hz each  [169MB/260MB 65%]
2023-04-12 14:43:28.812 INFO  i.g.d.d.f.c.ComplexPolyphaseChannelizerM2 - Sample Rate [2400000.0] providing [96] channels at [25000.0] Hz each  [182MB/260MB 70%]
2023-04-12 14:43:28.964 INFO  i.g.d.d.f.c.ComplexPolyphaseChannelizerM2 - Sample Rate [2400000.0] providing [96] channels at [25000.0] Hz each  [190MB/260MB 73%]
2023-04-12 14:43:29.273 INFO  i.g.d.d.f.c.ComplexPolyphaseChannelizerM2 - Sample Rate [2400000.0] providing [96] channels at [25000.0] Hz each  [233MB/680MB 34%]
2023-04-12 14:43:29.214 ERROR i.g.d.d.f.c.ComplexPolyphaseChannelizerM2 - Error during IFFT and dispatch of processed channel results  [236MB/680MB 34%]
java.lang.NullPointerException: Cannot load from float array because "in" is null
        at org.jtransforms.fft.FloatFFT_1D.passf4(FloatFFT_1D.java:7150)
        at org.jtransforms.fft.FloatFFT_1D.cfftf(FloatFFT_1D.java:6660)
        at org.jtransforms.fft.FloatFFT_1D.complexInverse(FloatFFT_1D.java:375)
        at org.jtransforms.fft.FloatFFT_1D.complexInverse(FloatFFT_1D.java:323)
        at io.github.dsheirer.dsp.filter.channelizer.ComplexPolyphaseChannelizerM2$IFFTProcessorDispatcher.lambda$new$0(ComplexPolyphaseChannelizerM2.java:425)
        at io.github.dsheirer.util.Dispatcher.process(Dispatcher.java:182)
        at io.github.dsheirer.util.Dispatcher$Processor.run(Dispatcher.java:205)
        at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
        at java.base/java.util.concurrent.FutureTask.runAndReset(Unknown Source)
        at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source)
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
        at java.base/java.lang.Thread.run(Unknown Source)

Expected behavior

Channelizer's IFFTProcessor should check for null before invoking IFFT.