# punktfunk client UDP socket-buffer tuning. The client asks the kernel for a 32 MB UDP receive # buffer (SO_RCVBUF) so high-bitrate video bursts don't overflow it, but the kernel silently CLAMPS # the request to net.core.rmem_max — whose default (~208 KB-4 MB) is far too small. A too-small recv # buffer is the dominant client-side wall above ~1 Gbps: measured live, a 4 MB cap dropped 31.6% of a # 2 Gbps stream at the receiver while a 32 MB cap delivered the same 2 Gbps at 0.0% loss. wmem covers # the mic-uplink / input send side. systemd-sysctl applies this at boot; the postinst applies it now. net.core.rmem_max = 33554432 net.core.wmem_max = 33554432