During Shuttle/ISS missions, Shuttle talked down through TDRSS satellite, whereas Station typically talked through ground stations.
Even for not having to deal with the RF delays, the hop delays were enough that after Shuttle docked to Station, an umbilical was run through the hatch to connect the two Comm systems, and a setup called "The Big Loop" was enabled which allowed ISS to communicate using Shuttle's TDRSS system as Primary.
ISS radios were generally unused during docked operations, or used as back channels. Video however was always direct downlinked via Ku-band and it would go in and out of the coverage of ground stations.
Later upgrades to TDRSS provided (and still provide) data rates capable of hosting videoconferencing from the on-board PCs on the "WAN"... And crews even got private talk time with family and personal medical doc conferences over those links.
The Comm configuration of ISS also had to patch the space suits for construction and EVA activity back into "The Big Loop".
At times, when the wrong audio patches were selected, "The Big Loop" could go quite sideways. I heard it a few times via NASA Select/NASA TV audio feeds over the years.
One of the reasons I keep my GE MP/A boat-anchor handhelds (re-tuned for the Ham Radio bands... One each for VHF, UHF, and 900 MHz) is the historical -- the GE MP/A handheld attached to a custom adapter to a David Clark headset, was the first space qualified ham radio rig utilized aboard the Shuttle for their Ham Radio outreach program.
Some history of the Shuttle Amateur Radio Experiment (SAREX) and a photo of the MP/A and DC headset can be seen here:
http://spaceflight.nasa.gov/station/reference/radio
Sadly, while my first flight instructor worked the Shuttle and received a QSL card/gorgeous certificate, I never got around to doing it. Listened to them a number of times though. And tried to call in the "pile-ups" when many Astronauts operated during their personal time.
Later, both Shuttle and Station received Kenwood mobile rigs and packet radio digipeaters.
Hundreds of Ham Radio contacts between Shuttle/Station have been done with various school classrooms over the years. Friends have helped do the leg work on some of those. There's a lot of behind the scenes coordination, and I was proud to learn that a teleconferencing bridge built by my former employer was utilized heavily during those school contacts.
Only the archive.org folks now have the venerable old original NASA SAREX website, complete with HTML 1 tags, and that always ubiquitous "techy" black background... Heh...
http://web.archive.org/web/20030124194138/http://sarex.gsfc.nasa.gov/
Good times. Lots of memories. My former employer also provided a massive audio conference bridge setup for Discovery's first return to space mission, where thousands of classrooms listened into the launch, and had posters done up for it... mine hung in my home office for years and got damaged in a move.