Differences

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--- troubleshooting [2026/01/13 20:52] – walter
+++ troubleshooting [2026/02/18 20:11] (current) – sol
@@ Line 19: / Line 19: @@
 ===== NTSC 1702 monitor - only setting that works is NTSC-50.   =====
 when using my new U64 with a traditional NTSC 1702 monitor, I noticed the only setting that works is NTSC-50.  When I attempt to use the traditional/standard NTSC setting, the screen jumps up and down.  The 1702 monitor works fine with my vintage NTSC C64.
-  * Solution: both NTSC-50 and standard NSTC work fine, but I needed to make some manual adjustments via the horizontal and vertical hold on the 1702.
+  * **Solution:** both NTSC-50 and standard NSTC work fine, but I needed to make some manual adjustments via the horizontal and vertical hold on the 1702.
+===== Only left audio channel from 3.5mm jack while A/V jack connected   =====
+When an A/V cable with mono audio is connected to a CRT monitor, the 3.5 mm audio output on the Commodore 64 Ultimate only plays the left audio channel. If the A/V cable is unplugged, both left and right channels work normally through the 3.5 mm jack. Some original custom Commodore 64 A/V cables were wired so that AUDIO IN (pin 5) and GROUND (pin 2) are tied together to reduce interference. The Commodore 64 Ultimate, however, repurposes pin 5 as the right audio channel (see User's Guide p.205). When you plug in one of these older-style cables, pin 5 is shorted to ground and silencing the right channel entirely.
+  * **Solution:** Use an A/V cable designed specifically for the Commodore 64 Ultimate, or one that does not connect pin 5 to ground. Once the correct cable is used, both audio channels will work normally from the 3.5 mm output.
+{{tag>troubleshooting GEOS REU wifi audio}}
-{{tag>troubleshooting GEOS REU wifi}}