Did you bind it as toggle or hold? I don't have any issues and I have prone bound to Ctrl. Performance is very much improved lately with Squad, but I really don't like the direction of the art style any more. Before v8 the maps looked realistic, dull, dusty and gritty, with long draw distances etc. The soldier uniforms camouflaged nicely into them if you considered your approach. Since v8, everything is much more colourful and there are some more ambient mist and environmental effects which make Squad look more 'gamey'. Many of the factions now have uniforms that are inconsistently blended with the rest of the art style which leads to some soldiers appearing dark and silhouette like against the environment, not just because of the direction of the sunlight. Hopefully they fix this in the next patch because it is such a shame to not be concealed in long grass or fields anymore. Squad is a pigeon shooter right now.