I've finally been able to complete the tutorial flight (three times in a row) with no freezes or CTDs. Before today I have never even got half-way to Schiphol before the simulator freezed (not panel freeze, the whole sim hanged for me). The cause of my problems was, suprisingly, having my controllers connected via a USB hub. I had a CH yoke, CH throttle quadrant, Sidewinder steering wheel (which I actually use as rudder :) and a mouse all connected through a four port USB hub. After a gazillion reinstalls and config changes I decided to remove all controls and try with the yoke only. Suddenly all stability issues were gone! I've now added the steering wheel and the throttle quadrant, but skipped the hub itself and it still runs perfectly. The sim has worked smoothly using the USB hub when flying the default planes, the F1 cessna citation mustang, and a number of other addon planes, but failed completely with the PMDG 737 NGX. So if your NGX keeps freezing, you might want to try to connect your controllers directly to the computer and it just might solve the problem. -- Rickard Holgersson

I also tend to believe that there is an issue between usb hubs and the ngx. In my case my keyboard and my mouse are attached to a hub and every now and then but 99% of the time when i'm on short finals the ngx sound stops, there's a stutter or two and I can hear the faint sound of windows having a piece of hardware unplugged then replugged, and everything continues (with a ruined flare! @<%#$^!!!). Never had this before the ngx.

How many USB ports so you have?Try using a different USB controller hub for each piece of hardware ( ie; one at the front of the PC and one at the rear).Just a thought, perhaps one is on the way out?I occasionally have a problem with one of my USB ports on the front of my PC and this affects my Track IR.Dan.

As the NGX is a quite a bit more sophisticated than other commercial acft, quite a bit problems can arise from hardware items. I've read here a lot about freezes within the NGX community experience and the few I had were mere conflicts originated from a poorly configurated graphic unity or a sound issue - I observed that just before the freeze, I did something to demand a heavy graphic resource. We must have our attention on scenery, weather and traffic details just to remember the conditions that led to a crash. But talking about USB hubs, IMHO those should not be used for flying ;-) as the necessary equipment has powerful responses and deal with a complex electric environment. So, use your hub to plug a barcode reader or a bluetooth unity. Your joystick, throttles and pedals go straight into the main USB entries of the motherboard. Regards,

As the NGX is a quite a bit more sophisticated than other commercial acft, quite a bit problems can arise from hardware items. I've read here a lot about freezes within the NGX community experience and the few I had were mere conflicts originated from a poorly configurated graphic unity or a sound issue - I observed that just before the freeze, I did something to demand a heavy graphic resource. We must have our attention on scenery, weather and traffic details just to remember the conditions that led to a crash. But talking about USB hubs, IMHO those should not be used for flying ;-) as the necessary equipment has powerful responses and deal with a complex electric environment. So, use your hub to plug a barcode reader or a bluetooth unity. Your joystick, throttles and pedals go straight into the main USB entries of the motherboard. Regards,

Exactly, what I meant was the motherboard controller/hub, as each can only assign 500 mA, so if you use an external hub as well then with today's hardware throttles and yokes etc you will run into problems.Often the ports on the rear of the case are on a different bus from the ones at the front so a good way to split the load.I'm no expert but this is how I understand the USB architecture.Dan.

Should never use a hub on a controller, they dont play well together.