Where to begin. Pretty much everything is not working...

- With Sound Blaster 16, the audio (particularly music and the mission briefing speech) is very 'crackly'. I switched to Sound Blaster which seemed better. I managed to start a training mission and the game was fine. Next time I booted the game, after tinkering with the sound card options, the game crashed upon starting a training mission.
Now, every time I boot the game, there is no sound until I switch to a different sound card. Also, it will not load a training mission; the game just resets to desktop every time.

- Also, the opening logo splash-screens and intro cinematic have absolutely no sound whatsoever.

I'm using Windows 8.1 and have hardly ever had any trouble getting a dosbox game to run perfectly.
As you can tell, I'm having absolutely no luck here. It's very disappointing. Can anyone tell me where I'm possibly going wrong please?

As for the cinematics not having sound is because they were recorded without sound in the first place for some reason.
For your other issues I suggest you issue a supportticket, if they can't give a satisfactory resolution you could at least get your money back.

Thanks for the reply and for putting my mind at ease regarding the cinematics. I can easily live with that knowing it's supposed to be that way, and is not an actual fault.

I've just realised: The crashing when loading the stage was probably because I'd changed the compatibility settings to Windows 95 (that's when the crashes started), but I had forgotten to put them back the way they were.

The sound problem is a strange one. I've tried tinkering with the config file, tried varies sound card settings, compatibility settings, running as admin..... No improvement. In fact, when I tried adjusting the cycles, it made things worse! The adjustment caused the voices to sound like loud robots. When I set the cycles back to their original value this latest problem persisted until I rebooted; still, the lesser problem of 'crackling' audio in the menus remains, as does the game sometimes resetting the moment the sound card settings are changed.

Other than that, the game runs fine and is very enjoyable.

I rather had gog solve this issue themselves as their Dosbox configurations tend to be broken or badly optimized but I bought the game and ran into the same issues as you.
I think it's caused by gog altering the default Soundblaster IRQ from 7 to 5 which seems to conflict with the joystick.

Try replacing dosboxHIND.conf with this one I made.

Sorry for the late reply. I had tried altering the IRQ to 7. I can't remember if I did it via the configuration file or in-game (If that's possible). I haven't had the chance lately to try other tweaks. Thanks for your config file, I will test it out very soon and let you know the result :)

Thanks for your config file. I'm afraid sadly it didn't work for me. It did eliminate the crackling noise, but made the sound very muffled and distorted. Not sure what the cause of that could be.

Set and calibrate your joystick in the Preferences screen and see if you can edit the Soundblaster IRQ back and forth between 5 and 7, I had to do this a couple of times before I got rid of the soundproblem.

I've tried what you suggested. I still can't get it to work properly so far I'm afraid. Thanks for all of your efforts though, much appreciated. I'm sure I'm just missing something here. I'll keep trying with the alternating IRQ 5/7 thing nevertheless. If I get it to work, I'll mark yours as the solution.