diff --git a/TradeSkillMaster_AuctionDB/Modules/ChannelSync.lua b/TradeSkillMaster_AuctionDB/Modules/ChannelSync.lua
index d57e908..f1bd24e 100644
--- a/TradeSkillMaster_AuctionDB/Modules/ChannelSync.lua
+++ b/TradeSkillMaster_AuctionDB/Modules/ChannelSync.lua
@@ -33,6 +33,13 @@ local strbyte = string.byte
 local libS = LibStub:GetLibrary("AceSerializer-3.0")
 local libD = LibStub("LibDeflate", true)
 local warnedNoDeflate
+local debugEnabled = true
+
+local function DebugPrint(msg)
+	if debugEnabled then
+		TSM:Print("ChannelSync: " .. msg)
+	end
+end
 
 local function CanEncode()
 	if libD then return true end
@@ -89,19 +96,35 @@ end
 local function EncodePayload(payload)
 	if not CanEncode() then return end
 	local serialized = libS:Serialize(payload)
+	if not serialized then
+		DebugPrint("Serialize failed.")
+		return
+	end
 	local compressed = libD:CompressDeflate(serialized, { level = 9 })
-	if not compressed then return end
+	if not compressed then
+		DebugPrint("CompressDeflate failed.")
+		return
+	end
 	return libD:EncodeForPrint(compressed)
 end
 
 local function DecodePayload(encoded)
 	if not CanEncode() then return end
 	local decoded = libD:DecodeForPrint(encoded)
-	if not decoded then return end
+	if not decoded then
+		DebugPrint("DecodeForPrint failed.")
+		return
+	end
 	local decompressed = libD:DecompressDeflate(decoded)
-	if not decompressed then return end
+	if not decompressed then
+		DebugPrint("DecompressDeflate failed.")
+		return
+	end
 	local ok, payload = libS:Deserialize(decompressed)
-	if not ok then return end
+	if not ok then
+		DebugPrint("Deserialize failed.")
+		return
+	end
 	return payload
 end
 
@@ -123,10 +146,10 @@ function ChannelSync:BroadcastScanData(scanType, items)
 
 	local function QueueEncoded(encoded)
 		local hash = HashString(encoded)
-		if hash == private.lastBroadcastHash then return end
-		private.lastBroadcastHash = hash
-		local total = ceil(#encoded / CHUNK_SIZE)
-		if total > MAX_TOTAL_CHUNKS then return false end
+	if hash == private.lastBroadcastHash then return end
+	private.lastBroadcastHash = hash
+	local total = ceil(#encoded / CHUNK_SIZE)
+	if total > MAX_TOTAL_CHUNKS then return false end
 		tinsert(private.sendQueue, {hash = hash, encoded = encoded, total = total})
 		if not private.isSending then
 			private.isSending = true
@@ -264,7 +287,9 @@ local function MergeIncomingData(payload, sender)
 
 	TSM:Serialize()
 
-	if updated > 0 and sender then
+	if updated == 0 and sender then
+		DebugPrint("No items updated from " .. sender .. ".")
+	elseif updated > 0 and sender then
 		if updated == 1 and lastItemID then
 			local link = select(2, GetItemInfo(lastItemID)) or ("item:" .. tostring(lastItemID))
 			TSM:Printf("AuctionDB updated %s from %s.", link, sender)
@@ -295,11 +320,15 @@ function ChannelSync:OnChannelMessage(_, msg, source, _, _, _, _, _, channelName
 
 	local bundle = private.incoming[hash]
 	if not bundle or (time() - bundle.time) > BUNDLE_TIMEOUT then
+		if bundle then
+			DebugPrint("Bundle timeout " .. format("%08x", hash) .. " (" .. bundle.received .. "/" .. bundle.total .. ").")
+		end
 		bundle = {time = time(), total = total, chunks = {}, received = 0}
 		private.incoming[hash] = bundle
 	end
 
 	if bundle.total ~= total then
+		DebugPrint("Bundle total mismatch for " .. format("%08x", hash) .. ". Resetting.")
 		private.incoming[hash] = {time = time(), total = total, chunks = {}, received = 0}
 		bundle = private.incoming[hash]
 	end
@@ -319,7 +348,10 @@ function ChannelSync:OnChannelMessage(_, msg, source, _, _, _, _, _, channelName
 	private.incoming[hash] = nil
 
 	local payload = DecodePayload(table.concat(parts))
-	if not payload then return end
+	if not payload then
+		DebugPrint("Payload decode failed for bundle " .. format("%08x", hash))
+		return
+	end
 	MergeIncomingData(payload, source)
 end
 
@@ -332,6 +364,7 @@ function ChannelSync:SendQueueThread()
 			SendChatMessage(msg, "CHANNEL", nil, private.channelId)
 			self:Sleep(SEND_INTERVAL)
 		end
+		DebugPrint("Sent bundle " .. format("%08x", job.hash) .. " (" .. job.total .. " chunks).")
 		tremove(private.sendQueue, 1)
 	end
 	private.isSending = false