so ive been trying to get winlink running properly for about three weeks now and im losing my mind a little bit. the basic setup is working — i can connect to an RMS gateway, handshake goes fine, but somewhere in the middle of actually transferring a message it just drops. doesnt matter if its a short message or longer one with an attachment, though the attachment ones fail way faster.

running vara HF on a IC-7300 with the USB cable doing both audio and CAT, soundcard is set up in vara as the IC-7300 built in codec. level seems okay, i had it peaking around -10 to -12 on the vara waterfall. ALC is barely moving on the radio which i thought was the right approach.

the winlink client is RMS express, latest version i think, and i can see in the session log it gets through the handshake and starts the transfer then just kind of stops. the gateway doesnt send a disconnect message, it just goes silent and eventually my side times out. i tried two different gateways and same behavior on both which makes me think its something on my end but i cant figure out what.

anyone dealt with this or have a clue where to start? been reading the winlink wiki and honestly its a lot to absorb

this sounds familiar actually, i had almost the exact same thing happening when i first set up vara hf. turned out my USB cable was garbage — was getting tiny ground loop artifacts that you could barely see on the waterfall but they were enough to corrupt the data stream mid-transfer. swapped to a shielded cable with ferrites on both ends and it mostly went away.

also check your windows sound settings, make sure nothing else is grabbing the audio device. had a discord notification sound literally break a session once because windows decided to route it through the same device. exclusive mode in the sound control panel helped. and if you're on a laptop check if any power saving stuff is throttling the USB ports, that was another one that bit me.

the ALC thing you mentioned — yeah keep it barely moving, you're on the right track there. vara hf is pretty sensitive to overdrive and the artifacts it causes are not always obvious on the signal meter but they kill the protocol.

what band are you trying this on? some of the gateways are super busy on 40 especially in the evenings and i've noticed some of them seem to silently drop connections when they get hammered. not saying thats definitely your issue but worth trying a less busy one or hitting it at a weird hour to see if behavior changes.

also RMS express has a session log you can look at more carefully — like does it say anything after the transfer stops or does it literally just stop logging. theres usually a clue in there. if you can paste a few lines from around the failure point that would help narrow it down.