EQMOD randomly times out

[morayskies]

Hi All

Has anybody else had this problem?

I use a single, ageing laptop (HP620 8Gb RAM) running Windows 7 Pro 64bit to control my imaging setup using the following software;
Cartes du Ciel and EQMOD to control EQ5 Pro mount via EQDIRECT cable connected via powered USB Hub
BackyardEOS to capture images from Canon 450D via same USB powered hub
PHD2 for guiding using GP-CAM 130C and EQMOD pulse guiding

What confuses me is that some evenings everything works absolutely fine.  Another evening, using exactly the same hardware, software and even connections (ie I always plug the leads into the same ports) the system will be working fine but then suddenly fail.  The failure affects EQMOD indicating a timeout or port not available issue and the Canon 450D also 'locks' requiring a restart of the camera and BackyardEOS.

I have run USBTree during such a failure and it is showing that the EQDIRECT cable (ie serial converter) is still connected to COM4 (which is correct) and the Canon 450D is also still connected.  I basically have to ensure that all the software is closed and any associated services also stopped.  Of course, the scope is now pointing away from its home position so I have to move it manually back to 'home' before starting again.

My thoughts are that there could be a number of issues;
1. Use of a USB hub
2. A dodgy EQDIRECT cable
3. USB cables too long (ie about 5m)
4. Windows is turning off a connection (I have set the power management for each USB port to 'off')
5. Canon 450D somehow 'freezing'

When using this laptop, I turn off the Wifi and Anti Virus and Automatic Updates are also off.

It just baffles me that sometimes this system works flawlessly for hours and yet other nights it keeps failing.

Any suggestions gratefully received.

Thanks for looking.

[Tomatobro]

What power supply do you use? sounds like a voltage droop could be the issue.