S80 2001 nonturbo 108000 A/C cools until ambient temp gets

[Donfather]

S80 2001 nonturbo 108000 A/C cools until ambient temp get around 95 degrees then cuts out..Seems to perform better at hwy speed with increased ram air but eventually will cut out. The compressor has a themal sensor on the manifold has anyone heard of them going bad or bulletin about the A/C problem. Fully serviced system last summer and recently with this problem no change though any ideas??