QGIS » QGIS Application

I am working with a PostGIS layer which has 13 000+ records. I use Google Satelite imagery from the OpenLayers Plugin. I have one other PostGIS layer in the project and one other shapefile. While editing the PostGIS layer and saving multiple times, I have no problems. After about an hour (this varies) QGIS for some reason would start hanging when I try to save the edits on the PostGIS layer. After the first hang, it might respond again and manage to finish the save, but sometimes it doesn't and crashes completely. After the first hang, it could still work, but then it would nearly hang every time I save the PostGIS layer edits. I do not loose any data and no data becomes corrupt, but I have to restart QGIS then at least 5 times a day. I have checked the layer is indexed in PostGIS and it has the spatial reference information in the Geometry field. This is just a simple linestring.