Huge amount of mystic crashes of WP8 app

I've published an app with integrated hockeyapp. But Windows Phone dashboard crash report contains mystic crashes that are not in hockeyapp. According to stacktrace they are native (OS crashes).

App is 8.0 DirectX + Xaml app. Crashes are generated by 8.1 devices. 8.0 devices worked perfectly. I've tested app on all known WP devices for many hours on each, everything works perfectly. Seems some ocasianal bug in 8.1 :(

The biggest crash group is the following:

EXCEPTION_FAILFAST_ON_ERRORCODE_ERROR_CODE_88000837_BEDB185E-7ADE-48E5-B755-D7556882BD1B

Frame    Image                Function                                                                                              Offset        
0        KERNELBASE.dll       RaiseException                                                                                        0x00000036    
1        npctrl.dll           CXcpControl::CPReportError                                                                            0x00000066    
2        npctrl.dll           CXcpControl::ReportError                                                                              0x00000010    
3        npctrl.dll           CXcpDispatcher::OnError                                                                               0x000000c2    
4        npctrl.dll           CXcpDispatcher::OnWindowMessage                                                                       0x00011ba6    
5        npctrl.dll           CXcpDispatcher::GroupDispatchProcStatic                                                               0x0000011e    
6        CoreMessaging.dll    Microsoft__CoreUI__DispatchGroupHandler$CallbackThunk                                                 0x000000ca    
7        CoreMessaging.dll    Microsoft::CoreUI::DispatchGroupHandler::Invoke                                                       0x00000016    
8        CoreMessaging.dll    Microsoft::CoreUI::Dispatch::Dispatcher::Callback_DispatchLoop                                        0x00000746    
9        CoreMessaging.dll    Microsoft::CoreUI::Dispatch::EventLoop::Callback_Run                                                  0x0000007a    
10       CoreMessaging.dll    Microsoft::CoreUI::Messaging::MessageSession$R::Microsoft__CoreUI__IExportMessageSession_Impl::Run    0x0000002c    
11       CoreMessaging.dll    Microsoft::CoreUI::IExportMessageSession$X__ExportAdapter::Run                                        0x0000004e    
12       TaskHostCore.dll     HostDispatcher::Run                                                                                   0x000000a8    
13       TaskHostCore.dll     TaskHost::RunMessageLoop                                                                              0x00000016    
14       TaskHostCore.dll     ThRun                                                                                                 0x0000000e    
15       TaskHost.exe         wmain                                                                                                 0x00000016    
16       TaskHost.exe         __wmainCRTStartup                                                                                     0x000+H1:H2

Crash has attached minidmp for TaskHost.exe. Unfortunately i have no idea what can i get from it.

Any ideas what way i can go to fix the issue ?

Are you sure you're handling the Disconnect callback accordingly ? As in do you clear and reload all your resources after a Surface::Diconnect ? If you do not handle Disconnect at all, your app will crash on resume. If you do handle it and you're not doing it the proper way your app will start using more and more memory and will crash if it goes past 170MB or so.