I would open a ticket with our support team to check.
Provide all the details you mentioned here.
In addition to this, please generate and provide an RG report from the machine in the support case. An RG report helps us know how the modules are behaving on the machine when the hanging occurs. To do this: 1) Run the Report Generator tool located in <TestComplete>\x64\Bin\ReportGenerator.exe (for the 64-bit tool version) or <TestComplete>\Bin\ReportGenerator.exe (for the 32-bit tool version).
In your connection string, which DB driver/provider are you using to establish connection with your DB? Is it a 64-bit driver or 32-bit driver? If you are using 64-bit driver, you need to make sure that you are running 64-bit version of testcomplete(inside x64 folder in installation directory). If you are using a 32-bit driver, you should be running 32-bit version of testcomplete.